diff --git a/agent/config.go b/agent/config.go
index b4293e9e03..13024439dd 100644
--- a/agent/config.go
+++ b/agent/config.go
@@ -1,12 +1,12 @@
 package agent
 
 import (
-	"github.com/boltdb/bolt"
 	"github.com/docker/go-events"
 	"github.com/docker/swarmkit/agent/exec"
 	"github.com/docker/swarmkit/api"
 	"github.com/docker/swarmkit/connectionbroker"
 	"github.com/pkg/errors"
+	bolt "go.etcd.io/bbolt"
 	"google.golang.org/grpc/credentials"
 )
 
diff --git a/agent/storage.go b/agent/storage.go
index a49ad81fa4..519880197f 100644
--- a/agent/storage.go
+++ b/agent/storage.go
@@ -1,9 +1,9 @@
 package agent
 
 import (
-	"github.com/boltdb/bolt"
 	"github.com/docker/swarmkit/api"
 	"github.com/gogo/protobuf/proto"
+	bolt "go.etcd.io/bbolt"
 )
 
 // Layout:
diff --git a/agent/storage_test.go b/agent/storage_test.go
index b0ac1c6c45..8af7f4a800 100644
--- a/agent/storage_test.go
+++ b/agent/storage_test.go
@@ -8,10 +8,10 @@ import (
 	"sort"
 	"testing"
 
-	"github.com/boltdb/bolt"
 	"github.com/docker/swarmkit/api"
 	"github.com/docker/swarmkit/identity"
 	"github.com/stretchr/testify/assert"
+	bolt "go.etcd.io/bbolt"
 )
 
 func TestStorageInit(t *testing.T) {
diff --git a/agent/worker.go b/agent/worker.go
index 734a510715..8125145d21 100644
--- a/agent/worker.go
+++ b/agent/worker.go
@@ -3,12 +3,12 @@ package agent
 import (
 	"sync"
 
-	"github.com/boltdb/bolt"
 	"github.com/docker/swarmkit/agent/exec"
 	"github.com/docker/swarmkit/api"
 	"github.com/docker/swarmkit/log"
 	"github.com/docker/swarmkit/watch"
 	"github.com/sirupsen/logrus"
+	bolt "go.etcd.io/bbolt"
 	"golang.org/x/net/context"
 )
 
diff --git a/agent/worker_test.go b/agent/worker_test.go
index f75e925e71..f75335f8bf 100644
--- a/agent/worker_test.go
+++ b/agent/worker_test.go
@@ -3,12 +3,12 @@ package agent
 import (
 	"testing"
 
-	"github.com/boltdb/bolt"
 	"github.com/docker/swarmkit/agent/exec"
 	"github.com/docker/swarmkit/api"
 	"github.com/docker/swarmkit/log"
 	"github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/assert"
+	bolt "go.etcd.io/bbolt"
 	"golang.org/x/net/context"
 )
 
diff --git a/node/node.go b/node/node.go
index a3a762f380..6cbf265c5d 100644
--- a/node/node.go
+++ b/node/node.go
@@ -17,7 +17,6 @@ import (
 	"github.com/docker/swarmkit/ca/keyutils"
 	"github.com/docker/swarmkit/identity"
 
-	"github.com/boltdb/bolt"
 	"github.com/docker/docker/pkg/plugingetter"
 	metrics "github.com/docker/go-metrics"
 	"github.com/docker/swarmkit/agent"
@@ -35,6 +34,7 @@ import (
 	grpc_prometheus "github.com/grpc-ecosystem/go-grpc-prometheus"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
+	bolt "go.etcd.io/bbolt"
 	"golang.org/x/net/context"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials"
diff --git a/vendor.conf b/vendor.conf
index c86ff34a00..f91ea497e0 100644
--- a/vendor.conf
+++ b/vendor.conf
@@ -43,7 +43,6 @@ github.com/davecgh/go-spew 346938d642f2ec3594ed81d874461961cd0faa76 # v1.1.0
 github.com/Microsoft/go-winio v0.4.8
 github.com/sirupsen/logrus v1.0.3
 github.com/beorn7/perks 4c0e84591b9aa9e6dcfdf3e020114cd81f89d5f9
-github.com/boltdb/bolt fff57c100f4dea1905678da7e90d92429dff2904
 github.com/cloudflare/cfssl 1.3.2
 github.com/dustin/go-humanize 8929fe90cee4b2cb9deb468b51fb34eba64d1bf0
 github.com/fernet/fernet-go 1b2437bc582b3cfbb341ee5a29f8ef5b42912ff2
@@ -60,6 +59,7 @@ github.com/rcrowley/go-metrics 51425a2415d21afadfd55cd93432c0bc69e9598d
 github.com/spf13/cobra 8e91712f174ced10270cf66615e0a9127e7c4de5
 github.com/spf13/pflag 7f60f83a2c81bc3c3c0d5297f61ddfa68da9d3b7
 github.com/stretchr/testify v1.1.4
+go.etcd.io/bbolt v1.3.1-etcd.8
 golang.org/x/crypto 1a580b3eff7814fc9b40602fd35256c63b50f491
 golang.org/x/net 0ed95abb35c445290478a5348a7b38bb154135fd
 golang.org/x/sys 37707fdb30a5b38865cfb95e5aab41707daec7fd
diff --git a/vendor/github.com/boltdb/bolt/LICENSE b/vendor/go.etcd.io/bbolt/LICENSE
similarity index 100%
rename from vendor/github.com/boltdb/bolt/LICENSE
rename to vendor/go.etcd.io/bbolt/LICENSE
diff --git a/vendor/github.com/boltdb/bolt/README.md b/vendor/go.etcd.io/bbolt/README.md
similarity index 84%
rename from vendor/github.com/boltdb/bolt/README.md
rename to vendor/go.etcd.io/bbolt/README.md
index 2a69d95e78..6546fc01ac 100644
--- a/vendor/github.com/boltdb/bolt/README.md
+++ b/vendor/go.etcd.io/bbolt/README.md
@@ -1,5 +1,18 @@
-Bolt [![Coverage Status](https://coveralls.io/repos/boltdb/bolt/badge.svg?branch=master)](https://coveralls.io/r/boltdb/bolt?branch=master) [![GoDoc](https://godoc.org/github.com/boltdb/bolt?status.svg)](https://godoc.org/github.com/boltdb/bolt) ![Version](https://img.shields.io/badge/version-1.2.1-green.svg)
-====
+bbolt
+=====
+
+[![Go Report Card](https://goreportcard.com/badge/github.com/etcd-io/bbolt?style=flat-square)](https://goreportcard.com/report/github.com/etcd-io/bbolt)
+[![Coverage](https://codecov.io/gh/etcd-io/bbolt/branch/master/graph/badge.svg)](https://codecov.io/gh/etcd-io/bbolt)
+[![Build Status Travis](https://img.shields.io/travis/etcd-io/bboltlabs.svg?style=flat-square&&branch=master)](https://travis-ci.com/etcd-io/bbolt)
+[![Godoc](http://img.shields.io/badge/go-documentation-blue.svg?style=flat-square)](https://godoc.org/github.com/etcd-io/bbolt)
+[![Releases](https://img.shields.io/github/release/etcd-io/bbolt/all.svg?style=flat-square)](https://github.com/etcd-io/bbolt/releases)
+[![LICENSE](https://img.shields.io/github/license/etcd-io/bbolt.svg?style=flat-square)](https://github.com/etcd-io/bbolt/blob/master/LICENSE)
+
+bbolt is a fork of [Ben Johnson's][gh_ben] [Bolt][bolt] key/value
+store. The purpose of this fork is to provide the Go community with an active
+maintenance and development target for Bolt; the goal is improved reliability
+and stability. bbolt includes bug fixes, performance enhancements, and features
+not found in Bolt while preserving backwards compatibility with the Bolt API.
 
 Bolt is a pure Go key/value store inspired by [Howard Chu's][hyc_symas]
 [LMDB project][lmdb]. The goal of the project is to provide a simple,
@@ -10,6 +23,8 @@ Since Bolt is meant to be used as such a low-level piece of functionality,
 simplicity is key. The API will be small and only focus on getting values
 and setting values. That's it.
 
+[gh_ben]: https://github.com/benbjohnson
+[bolt]: https://github.com/boltdb/bolt
 [hyc_symas]: https://twitter.com/hyc_symas
 [lmdb]: http://symas.com/mdb/
 
@@ -17,40 +32,46 @@ and setting values. That's it.
 
 Bolt is stable, the API is fixed, and the file format is fixed. Full unit
 test coverage and randomized black box testing are used to ensure database
-consistency and thread safety. Bolt is currently in high-load production
+consistency and thread safety. Bolt is currently used in high-load production
 environments serving databases as large as 1TB. Many companies such as
 Shopify and Heroku use Bolt-backed services every day.
 
+## Project versioning
+
+bbolt uses [semantic versioning](http://semver.org).
+API should not change between patch and minor releases.
+New minor versions may add additional features to the API.
+
 ## Table of Contents
 
-- [Getting Started](#getting-started)
-  - [Installing](#installing)
-  - [Opening a database](#opening-a-database)
-  - [Transactions](#transactions)
-    - [Read-write transactions](#read-write-transactions)
-    - [Read-only transactions](#read-only-transactions)
-    - [Batch read-write transactions](#batch-read-write-transactions)
-    - [Managing transactions manually](#managing-transactions-manually)
-  - [Using buckets](#using-buckets)
-  - [Using key/value pairs](#using-keyvalue-pairs)
-  - [Autoincrementing integer for the bucket](#autoincrementing-integer-for-the-bucket)
-  - [Iterating over keys](#iterating-over-keys)
-    - [Prefix scans](#prefix-scans)
-    - [Range scans](#range-scans)
-    - [ForEach()](#foreach)
-  - [Nested buckets](#nested-buckets)
-  - [Database backups](#database-backups)
-  - [Statistics](#statistics)
-  - [Read-Only Mode](#read-only-mode)
-  - [Mobile Use (iOS/Android)](#mobile-use-iosandroid)
-- [Resources](#resources)
-- [Comparison with other databases](#comparison-with-other-databases)
-  - [Postgres, MySQL, & other relational databases](#postgres-mysql--other-relational-databases)
-  - [LevelDB, RocksDB](#leveldb-rocksdb)
-  - [LMDB](#lmdb)
-- [Caveats & Limitations](#caveats--limitations)
-- [Reading the Source](#reading-the-source)
-- [Other Projects Using Bolt](#other-projects-using-bolt)
+  - [Getting Started](#getting-started)
+    - [Installing](#installing)
+    - [Opening a database](#opening-a-database)
+    - [Transactions](#transactions)
+      - [Read-write transactions](#read-write-transactions)
+      - [Read-only transactions](#read-only-transactions)
+      - [Batch read-write transactions](#batch-read-write-transactions)
+      - [Managing transactions manually](#managing-transactions-manually)
+    - [Using buckets](#using-buckets)
+    - [Using key/value pairs](#using-keyvalue-pairs)
+    - [Autoincrementing integer for the bucket](#autoincrementing-integer-for-the-bucket)
+    - [Iterating over keys](#iterating-over-keys)
+      - [Prefix scans](#prefix-scans)
+      - [Range scans](#range-scans)
+      - [ForEach()](#foreach)
+    - [Nested buckets](#nested-buckets)
+    - [Database backups](#database-backups)
+    - [Statistics](#statistics)
+    - [Read-Only Mode](#read-only-mode)
+    - [Mobile Use (iOS/Android)](#mobile-use-iosandroid)
+  - [Resources](#resources)
+  - [Comparison with other databases](#comparison-with-other-databases)
+    - [Postgres, MySQL, & other relational databases](#postgres-mysql--other-relational-databases)
+    - [LevelDB, RocksDB](#leveldb-rocksdb)
+    - [LMDB](#lmdb)
+  - [Caveats & Limitations](#caveats--limitations)
+  - [Reading the Source](#reading-the-source)
+  - [Other Projects Using Bolt](#other-projects-using-bolt)
 
 ## Getting Started
 
@@ -59,13 +80,28 @@ Shopify and Heroku use Bolt-backed services every day.
 To start using Bolt, install Go and run `go get`:
 
 ```sh
-$ go get github.com/boltdb/bolt/...
+$ go get go.etcd.io/bbolt/...
 ```
 
 This will retrieve the library and install the `bolt` command line utility into
 your `$GOBIN` path.
 
 
+### Importing bbolt
+
+To use bbolt as an embedded key-value store, import as:
+
+```go
+import bolt "go.etcd.io/bbolt"
+
+db, err := bolt.Open(path, 0666, nil)
+if err != nil {
+  return err
+}
+defer db.Close()
+```
+
+
 ### Opening a database
 
 The top-level object in Bolt is a `DB`. It is represented as a single file on
@@ -79,7 +115,7 @@ package main
 import (
 	"log"
 
-	"github.com/boltdb/bolt"
+	bolt "go.etcd.io/bbolt"
 )
 
 func main() {
@@ -395,7 +431,7 @@ db.View(func(tx *bolt.Tx) error {
 	c := tx.Bucket([]byte("MyBucket")).Cursor()
 
 	prefix := []byte("1234")
-	for k, v := c.Seek(prefix); bytes.HasPrefix(k, prefix); k, v = c.Next() {
+	for k, v := c.Seek(prefix); k != nil && bytes.HasPrefix(k, prefix); k, v = c.Next() {
 		fmt.Printf("key=%s, value=%s\n", k, v)
 	}
 
@@ -464,6 +500,55 @@ func (*Bucket) CreateBucketIfNotExists(key []byte) (*Bucket, error)
 func (*Bucket) DeleteBucket(key []byte) error
 ```
 
+Say you had a multi-tenant application where the root level bucket was the account bucket. Inside of this bucket was a sequence of accounts which themselves are buckets. And inside the sequence bucket you could have many buckets pertaining to the Account itself (Users, Notes, etc) isolating the information into logical groupings.
+
+```go
+
+// createUser creates a new user in the given account.
+func createUser(accountID int, u *User) error {
+    // Start the transaction.
+    tx, err := db.Begin(true)
+    if err != nil {
+        return err
+    }
+    defer tx.Rollback()
+
+    // Retrieve the root bucket for the account.
+    // Assume this has already been created when the account was set up.
+    root := tx.Bucket([]byte(strconv.FormatUint(accountID, 10)))
+
+    // Setup the users bucket.
+    bkt, err := root.CreateBucketIfNotExists([]byte("USERS"))
+    if err != nil {
+        return err
+    }
+
+    // Generate an ID for the new user.
+    userID, err := bkt.NextSequence()
+    if err != nil {
+        return err
+    }
+    u.ID = userID
+
+    // Marshal and save the encoded user.
+    if buf, err := json.Marshal(u); err != nil {
+        return err
+    } else if err := bkt.Put([]byte(strconv.FormatUint(u.ID, 10)), buf); err != nil {
+        return err
+    }
+
+    // Commit the transaction.
+    if err := tx.Commit(); err != nil {
+        return err
+    }
+
+    return nil
+}
+
+```
+
+
+
 
 ### Database backups
 
@@ -473,7 +558,7 @@ this from a read-only transaction, it will perform a hot backup and not block
 your other database reads and writes.
 
 By default, it will use a regular file handle which will utilize the operating
-system's page cache. See the [`Tx`](https://godoc.org/github.com/boltdb/bolt#Tx)
+system's page cache. See the [`Tx`](https://godoc.org/go.etcd.io/bbolt#Tx)
 documentation for information about optimizing for larger-than-RAM datasets.
 
 One common use case is to backup over HTTP so you can use tools like `cURL` to
@@ -719,6 +804,9 @@ Here are a few things to note when evaluating and using Bolt:
   can be reused by a new page or can be unmapped from virtual memory and you'll
   see an `unexpected fault address` panic when accessing it.
 
+* Bolt uses an exclusive write lock on the database file so it cannot be
+  shared by multiple processes.
+
 * Be careful when using `Bucket.FillPercent`. Setting a high fill percent for
   buckets that have random inserts will cause your database to have very poor
   page utilization.
@@ -759,7 +847,7 @@ Here are a few things to note when evaluating and using Bolt:
 
 ## Reading the Source
 
-Bolt is a relatively small code base (<3KLOC) for an embedded, serializable,
+Bolt is a relatively small code base (<5KLOC) for an embedded, serializable,
 transactional key/value database so it can be a good starting point for people
 interested in how databases work.
 
@@ -811,47 +899,55 @@ them via pull request.
 
 Below is a list of public, open source projects that use Bolt:
 
-* [BoltDbWeb](https://github.com/evnix/boltdbweb) - A web based GUI for BoltDB files.
-* [Operation Go: A Routine Mission](http://gocode.io) - An online programming game for Golang using Bolt for user accounts and a leaderboard.
+* [Algernon](https://github.com/xyproto/algernon) - A HTTP/2 web server with built-in support for Lua. Uses BoltDB as the default database backend.
 * [Bazil](https://bazil.org/) - A file system that lets your data reside where it is most convenient for it to reside.
-* [DVID](https://github.com/janelia-flyem/dvid) - Added Bolt as optional storage engine and testing it against Basho-tuned leveldb.
-* [Skybox Analytics](https://github.com/skybox/skybox) - A standalone funnel analysis tool for web analytics.
-* [Scuttlebutt](https://github.com/benbjohnson/scuttlebutt) - Uses Bolt to store and process all Twitter mentions of GitHub projects.
-* [Wiki](https://github.com/peterhellberg/wiki) - A tiny wiki using Goji, BoltDB and Blackfriday.
+* [bolter](https://github.com/hasit/bolter) - Command-line app for viewing BoltDB file in your terminal.
+* [boltcli](https://github.com/spacewander/boltcli) - the redis-cli for boltdb with Lua script support.
+* [BoltHold](https://github.com/timshannon/bolthold) - An embeddable NoSQL store for Go types built on BoltDB
+* [BoltStore](https://github.com/yosssi/boltstore) - Session store using Bolt.
+* [Boltdb Boilerplate](https://github.com/bobintornado/boltdb-boilerplate) - Boilerplate wrapper around bolt aiming to make simple calls one-liners.
+* [BoltDbWeb](https://github.com/evnix/boltdbweb) - A web based GUI for BoltDB files.
+* [bleve](http://www.blevesearch.com/) - A pure Go search engine similar to ElasticSearch that uses Bolt as the default storage backend.
+* [btcwallet](https://github.com/btcsuite/btcwallet) - A bitcoin wallet.
+* [buckets](https://github.com/joyrexus/buckets) - a bolt wrapper streamlining
+  simple tx and key scans.
+* [cayley](https://github.com/google/cayley) - Cayley is an open-source graph database using Bolt as optional backend.
 * [ChainStore](https://github.com/pressly/chainstore) - Simple key-value interface to a variety of storage engines organized as a chain of operations.
-* [MetricBase](https://github.com/msiebuhr/MetricBase) - Single-binary version of Graphite.
-* [Gitchain](https://github.com/gitchain/gitchain) - Decentralized, peer-to-peer Git repositories aka "Git meets Bitcoin".
+* [Consul](https://github.com/hashicorp/consul) - Consul is service discovery and configuration made easy. Distributed, highly available, and datacenter-aware.
+* [DVID](https://github.com/janelia-flyem/dvid) - Added Bolt as optional storage engine and testing it against Basho-tuned leveldb.
+* [dcrwallet](https://github.com/decred/dcrwallet) - A wallet for the Decred cryptocurrency.
+* [drive](https://github.com/odeke-em/drive) - drive is an unofficial Google Drive command line client for \*NIX operating systems.
 * [event-shuttle](https://github.com/sclasen/event-shuttle) - A Unix system service to collect and reliably deliver messages to Kafka.
+* [Freehold](http://tshannon.bitbucket.org/freehold/) - An open, secure, and lightweight platform for your files and data.
+* [Go Report Card](https://goreportcard.com/) - Go code quality report cards as a (free and open source) service.
+* [GoWebApp](https://github.com/josephspurrier/gowebapp) - A basic MVC web application in Go using BoltDB.
+* [GoShort](https://github.com/pankajkhairnar/goShort) - GoShort is a URL shortener written in Golang and BoltDB for persistent key/value storage and for routing it's using high performent HTTPRouter.
+* [gopherpit](https://github.com/gopherpit/gopherpit) - A web service to manage Go remote import paths with custom domains
+* [Gitchain](https://github.com/gitchain/gitchain) - Decentralized, peer-to-peer Git repositories aka "Git meets Bitcoin".
+* [InfluxDB](https://influxdata.com) - Scalable datastore for metrics, events, and real-time analytics.
+* [ipLocator](https://github.com/AndreasBriese/ipLocator) - A fast ip-geo-location-server using bolt with bloom filters.
 * [ipxed](https://github.com/kelseyhightower/ipxed) - Web interface and api for ipxed.
-* [BoltStore](https://github.com/yosssi/boltstore) - Session store using Bolt.
-* [photosite/session](https://godoc.org/bitbucket.org/kardianos/photosite/session) - Sessions for a photo viewing site.
+* [Ironsmith](https://github.com/timshannon/ironsmith) - A simple, script-driven continuous integration (build - > test -> release) tool, with no external dependencies
+* [Kala](https://github.com/ajvb/kala) - Kala is a modern job scheduler optimized to run on a single node. It is persistent, JSON over HTTP API, ISO 8601 duration notation, and dependent jobs.
 * [LedisDB](https://github.com/siddontang/ledisdb) - A high performance NoSQL, using Bolt as optional storage.
-* [ipLocator](https://github.com/AndreasBriese/ipLocator) - A fast ip-geo-location-server using bolt with bloom filters.
-* [cayley](https://github.com/google/cayley) - Cayley is an open-source graph database using Bolt as optional backend.
-* [bleve](http://www.blevesearch.com/) - A pure Go search engine similar to ElasticSearch that uses Bolt as the default storage backend.
-* [tentacool](https://github.com/optiflows/tentacool) - REST api server to manage system stuff (IP, DNS, Gateway...) on a linux server.
-* [Seaweed File System](https://github.com/chrislusf/seaweedfs) - Highly scalable distributed key~file system with O(1) disk read.
-* [InfluxDB](https://influxdata.com) - Scalable datastore for metrics, events, and real-time analytics.
-* [Freehold](http://tshannon.bitbucket.org/freehold/) - An open, secure, and lightweight platform for your files and data.
+* [lru](https://github.com/crowdriff/lru) - Easy to use Bolt-backed Least-Recently-Used (LRU) read-through cache with chainable remote stores.
+* [mbuckets](https://github.com/abhigupta912/mbuckets) - A Bolt wrapper that allows easy operations on multi level (nested) buckets.
+* [MetricBase](https://github.com/msiebuhr/MetricBase) - Single-binary version of Graphite.
+* [MuLiFS](https://github.com/dankomiocevic/mulifs) - Music Library Filesystem creates a filesystem to organise your music files.
+* [Operation Go: A Routine Mission](http://gocode.io) - An online programming game for Golang using Bolt for user accounts and a leaderboard.
+* [photosite/session](https://godoc.org/bitbucket.org/kardianos/photosite/session) - Sessions for a photo viewing site.
 * [Prometheus Annotation Server](https://github.com/oliver006/prom_annotation_server) - Annotation server for PromDash & Prometheus service monitoring system.
-* [Consul](https://github.com/hashicorp/consul) - Consul is service discovery and configuration made easy. Distributed, highly available, and datacenter-aware.
-* [Kala](https://github.com/ajvb/kala) - Kala is a modern job scheduler optimized to run on a single node. It is persistent, JSON over HTTP API, ISO 8601 duration notation, and dependent jobs.
-* [drive](https://github.com/odeke-em/drive) - drive is an unofficial Google Drive command line client for \*NIX operating systems.
+* [reef-pi](https://github.com/reef-pi/reef-pi) - reef-pi is an award winning, modular, DIY reef tank controller using easy to learn electronics based on a Raspberry Pi.
+* [Request Baskets](https://github.com/darklynx/request-baskets) - A web service to collect arbitrary HTTP requests and inspect them via REST API or simple web UI, similar to [RequestBin](http://requestb.in/) service
+* [Seaweed File System](https://github.com/chrislusf/seaweedfs) - Highly scalable distributed key~file system with O(1) disk read.
 * [stow](https://github.com/djherbis/stow) -  a persistence manager for objects
   backed by boltdb.
-* [buckets](https://github.com/joyrexus/buckets) - a bolt wrapper streamlining
-  simple tx and key scans.
-* [mbuckets](https://github.com/abhigupta912/mbuckets) - A Bolt wrapper that allows easy operations on multi level (nested) buckets.
-* [Request Baskets](https://github.com/darklynx/request-baskets) - A web service to collect arbitrary HTTP requests and inspect them via REST API or simple web UI, similar to [RequestBin](http://requestb.in/) service
-* [Go Report Card](https://goreportcard.com/) - Go code quality report cards as a (free and open source) service.
-* [Boltdb Boilerplate](https://github.com/bobintornado/boltdb-boilerplate) - Boilerplate wrapper around bolt aiming to make simple calls one-liners.
-* [lru](https://github.com/crowdriff/lru) - Easy to use Bolt-backed Least-Recently-Used (LRU) read-through cache with chainable remote stores.
 * [Storm](https://github.com/asdine/storm) - Simple and powerful ORM for BoltDB.
-* [GoWebApp](https://github.com/josephspurrier/gowebapp) - A basic MVC web application in Go using BoltDB.
 * [SimpleBolt](https://github.com/xyproto/simplebolt) - A simple way to use BoltDB. Deals mainly with strings.
-* [Algernon](https://github.com/xyproto/algernon) - A HTTP/2 web server with built-in support for Lua. Uses BoltDB as the default database backend.
-* [MuLiFS](https://github.com/dankomiocevic/mulifs) - Music Library Filesystem creates a filesystem to organise your music files.
-* [GoShort](https://github.com/pankajkhairnar/goShort) - GoShort is a URL shortener written in Golang and BoltDB for persistent key/value storage and for routing it's using high performent HTTPRouter.
+* [Skybox Analytics](https://github.com/skybox/skybox) - A standalone funnel analysis tool for web analytics.
+* [Scuttlebutt](https://github.com/benbjohnson/scuttlebutt) - Uses Bolt to store and process all Twitter mentions of GitHub projects.
+* [tentacool](https://github.com/optiflows/tentacool) - REST api server to manage system stuff (IP, DNS, Gateway...) on a linux server.
 * [torrent](https://github.com/anacrolix/torrent) - Full-featured BitTorrent client package and utilities in Go. BoltDB is a storage backend in development.
+* [Wiki](https://github.com/peterhellberg/wiki) - A tiny wiki using Goji, BoltDB and Blackfriday.
 
 If you are using Bolt in a project please send a pull request to add it to the list.
diff --git a/vendor/github.com/boltdb/bolt/bolt_386.go b/vendor/go.etcd.io/bbolt/bolt_386.go
similarity index 95%
rename from vendor/github.com/boltdb/bolt/bolt_386.go
rename to vendor/go.etcd.io/bbolt/bolt_386.go
index 820d533c15..4d35ee7cf3 100644
--- a/vendor/github.com/boltdb/bolt/bolt_386.go
+++ b/vendor/go.etcd.io/bbolt/bolt_386.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0x7FFFFFFF // 2GB
diff --git a/vendor/github.com/boltdb/bolt/bolt_amd64.go b/vendor/go.etcd.io/bbolt/bolt_amd64.go
similarity index 95%
rename from vendor/github.com/boltdb/bolt/bolt_amd64.go
rename to vendor/go.etcd.io/bbolt/bolt_amd64.go
index 98fafdb47d..60a52dad56 100644
--- a/vendor/github.com/boltdb/bolt/bolt_amd64.go
+++ b/vendor/go.etcd.io/bbolt/bolt_amd64.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0xFFFFFFFFFFFF // 256TB
diff --git a/vendor/github.com/boltdb/bolt/bolt_arm.go b/vendor/go.etcd.io/bbolt/bolt_arm.go
similarity index 98%
rename from vendor/github.com/boltdb/bolt/bolt_arm.go
rename to vendor/go.etcd.io/bbolt/bolt_arm.go
index 7e5cb4b941..105d27ddb7 100644
--- a/vendor/github.com/boltdb/bolt/bolt_arm.go
+++ b/vendor/go.etcd.io/bbolt/bolt_arm.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import "unsafe"
 
diff --git a/vendor/github.com/boltdb/bolt/bolt_arm64.go b/vendor/go.etcd.io/bbolt/bolt_arm64.go
similarity index 95%
rename from vendor/github.com/boltdb/bolt/bolt_arm64.go
rename to vendor/go.etcd.io/bbolt/bolt_arm64.go
index b26d84f91b..f5aa2a5ee2 100644
--- a/vendor/github.com/boltdb/bolt/bolt_arm64.go
+++ b/vendor/go.etcd.io/bbolt/bolt_arm64.go
@@ -1,6 +1,6 @@
 // +build arm64
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0xFFFFFFFFFFFF // 256TB
diff --git a/vendor/github.com/boltdb/bolt/bolt_linux.go b/vendor/go.etcd.io/bbolt/bolt_linux.go
similarity index 91%
rename from vendor/github.com/boltdb/bolt/bolt_linux.go
rename to vendor/go.etcd.io/bbolt/bolt_linux.go
index 2b67666140..7707bcacf0 100644
--- a/vendor/github.com/boltdb/bolt/bolt_linux.go
+++ b/vendor/go.etcd.io/bbolt/bolt_linux.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"syscall"
diff --git a/vendor/go.etcd.io/bbolt/bolt_mips64x.go b/vendor/go.etcd.io/bbolt/bolt_mips64x.go
new file mode 100644
index 0000000000..baeb289fd9
--- /dev/null
+++ b/vendor/go.etcd.io/bbolt/bolt_mips64x.go
@@ -0,0 +1,12 @@
+// +build mips64 mips64le
+
+package bbolt
+
+// maxMapSize represents the largest mmap size supported by Bolt.
+const maxMapSize = 0x8000000000 // 512GB
+
+// maxAllocSize is the size used when creating array pointers.
+const maxAllocSize = 0x7FFFFFFF
+
+// Are unaligned load/stores broken on this arch?
+var brokenUnaligned = false
diff --git a/vendor/go.etcd.io/bbolt/bolt_mipsx.go b/vendor/go.etcd.io/bbolt/bolt_mipsx.go
new file mode 100644
index 0000000000..2d9b1a91f3
--- /dev/null
+++ b/vendor/go.etcd.io/bbolt/bolt_mipsx.go
@@ -0,0 +1,12 @@
+// +build mips mipsle
+
+package bbolt
+
+// maxMapSize represents the largest mmap size supported by Bolt.
+const maxMapSize = 0x40000000 // 1GB
+
+// maxAllocSize is the size used when creating array pointers.
+const maxAllocSize = 0xFFFFFFF
+
+// Are unaligned load/stores broken on this arch?
+var brokenUnaligned = false
diff --git a/vendor/github.com/boltdb/bolt/bolt_openbsd.go b/vendor/go.etcd.io/bbolt/bolt_openbsd.go
similarity index 97%
rename from vendor/github.com/boltdb/bolt/bolt_openbsd.go
rename to vendor/go.etcd.io/bbolt/bolt_openbsd.go
index 7058c3d734..d7f50358ef 100644
--- a/vendor/github.com/boltdb/bolt/bolt_openbsd.go
+++ b/vendor/go.etcd.io/bbolt/bolt_openbsd.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"syscall"
diff --git a/vendor/github.com/boltdb/bolt/bolt_ppc.go b/vendor/go.etcd.io/bbolt/bolt_ppc.go
similarity index 69%
rename from vendor/github.com/boltdb/bolt/bolt_ppc.go
rename to vendor/go.etcd.io/bbolt/bolt_ppc.go
index 645ddc3edc..69804714aa 100644
--- a/vendor/github.com/boltdb/bolt/bolt_ppc.go
+++ b/vendor/go.etcd.io/bbolt/bolt_ppc.go
@@ -1,9 +1,12 @@
 // +build ppc
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0x7FFFFFFF // 2GB
 
 // maxAllocSize is the size used when creating array pointers.
 const maxAllocSize = 0xFFFFFFF
+
+// Are unaligned load/stores broken on this arch?
+var brokenUnaligned = false
diff --git a/vendor/github.com/boltdb/bolt/bolt_ppc64.go b/vendor/go.etcd.io/bbolt/bolt_ppc64.go
similarity index 70%
rename from vendor/github.com/boltdb/bolt/bolt_ppc64.go
rename to vendor/go.etcd.io/bbolt/bolt_ppc64.go
index 2dc6be02e3..3565908576 100644
--- a/vendor/github.com/boltdb/bolt/bolt_ppc64.go
+++ b/vendor/go.etcd.io/bbolt/bolt_ppc64.go
@@ -1,9 +1,12 @@
 // +build ppc64
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0xFFFFFFFFFFFF // 256TB
 
 // maxAllocSize is the size used when creating array pointers.
 const maxAllocSize = 0x7FFFFFFF
+
+// Are unaligned load/stores broken on this arch?
+var brokenUnaligned = false
diff --git a/vendor/github.com/boltdb/bolt/bolt_ppc64le.go b/vendor/go.etcd.io/bbolt/bolt_ppc64le.go
similarity index 95%
rename from vendor/github.com/boltdb/bolt/bolt_ppc64le.go
rename to vendor/go.etcd.io/bbolt/bolt_ppc64le.go
index 8c143bc5d1..422c7c69d6 100644
--- a/vendor/github.com/boltdb/bolt/bolt_ppc64le.go
+++ b/vendor/go.etcd.io/bbolt/bolt_ppc64le.go
@@ -1,6 +1,6 @@
 // +build ppc64le
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0xFFFFFFFFFFFF // 256TB
diff --git a/vendor/github.com/boltdb/bolt/bolt_s390x.go b/vendor/go.etcd.io/bbolt/bolt_s390x.go
similarity index 95%
rename from vendor/github.com/boltdb/bolt/bolt_s390x.go
rename to vendor/go.etcd.io/bbolt/bolt_s390x.go
index d7c39af925..6d3fcb825d 100644
--- a/vendor/github.com/boltdb/bolt/bolt_s390x.go
+++ b/vendor/go.etcd.io/bbolt/bolt_s390x.go
@@ -1,6 +1,6 @@
 // +build s390x
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0xFFFFFFFFFFFF // 256TB
diff --git a/vendor/github.com/boltdb/bolt/bolt_unix.go b/vendor/go.etcd.io/bbolt/bolt_unix.go
similarity index 71%
rename from vendor/github.com/boltdb/bolt/bolt_unix.go
rename to vendor/go.etcd.io/bbolt/bolt_unix.go
index cad62dda1e..5f2bb51451 100644
--- a/vendor/github.com/boltdb/bolt/bolt_unix.go
+++ b/vendor/go.etcd.io/bbolt/bolt_unix.go
@@ -1,41 +1,43 @@
 // +build !windows,!plan9,!solaris
 
-package bolt
+package bbolt
 
 import (
 	"fmt"
-	"os"
 	"syscall"
 	"time"
 	"unsafe"
 )
 
 // flock acquires an advisory lock on a file descriptor.
-func flock(db *DB, mode os.FileMode, exclusive bool, timeout time.Duration) error {
+func flock(db *DB, exclusive bool, timeout time.Duration) error {
 	var t time.Time
+	if timeout != 0 {
+		t = time.Now()
+	}
+	fd := db.file.Fd()
+	flag := syscall.LOCK_NB
+	if exclusive {
+		flag |= syscall.LOCK_EX
+	} else {
+		flag |= syscall.LOCK_SH
+	}
 	for {
-		// If we're beyond our timeout then return an error.
-		// This can only occur after we've attempted a flock once.
-		if t.IsZero() {
-			t = time.Now()
-		} else if timeout > 0 && time.Since(t) > timeout {
-			return ErrTimeout
-		}
-		flag := syscall.LOCK_SH
-		if exclusive {
-			flag = syscall.LOCK_EX
-		}
-
-		// Otherwise attempt to obtain an exclusive lock.
-		err := syscall.Flock(int(db.file.Fd()), flag|syscall.LOCK_NB)
+		// Attempt to obtain an exclusive lock.
+		err := syscall.Flock(int(fd), flag)
 		if err == nil {
 			return nil
 		} else if err != syscall.EWOULDBLOCK {
 			return err
 		}
 
+		// If we timed out then return an error.
+		if timeout != 0 && time.Since(t) > timeout-flockRetryTimeout {
+			return ErrTimeout
+		}
+
 		// Wait for a bit and try again.
-		time.Sleep(50 * time.Millisecond)
+		time.Sleep(flockRetryTimeout)
 	}
 }
 
@@ -53,7 +55,9 @@ func mmap(db *DB, sz int) error {
 	}
 
 	// Advise the kernel that the mmap is accessed randomly.
-	if err := madvise(b, syscall.MADV_RANDOM); err != nil {
+	err = madvise(b, syscall.MADV_RANDOM)
+	if err != nil && err != syscall.ENOSYS {
+		// Ignore not implemented error in kernel because it still works.
 		return fmt.Errorf("madvise: %s", err)
 	}
 
diff --git a/vendor/github.com/boltdb/bolt/bolt_unix_solaris.go b/vendor/go.etcd.io/bbolt/bolt_unix_solaris.go
similarity index 70%
rename from vendor/github.com/boltdb/bolt/bolt_unix_solaris.go
rename to vendor/go.etcd.io/bbolt/bolt_unix_solaris.go
index 307bf2b3ee..babad65786 100644
--- a/vendor/github.com/boltdb/bolt/bolt_unix_solaris.go
+++ b/vendor/go.etcd.io/bbolt/bolt_unix_solaris.go
@@ -1,8 +1,7 @@
-package bolt
+package bbolt
 
 import (
 	"fmt"
-	"os"
 	"syscall"
 	"time"
 	"unsafe"
@@ -11,36 +10,35 @@ import (
 )
 
 // flock acquires an advisory lock on a file descriptor.
-func flock(db *DB, mode os.FileMode, exclusive bool, timeout time.Duration) error {
+func flock(db *DB, exclusive bool, timeout time.Duration) error {
 	var t time.Time
+	if timeout != 0 {
+		t = time.Now()
+	}
+	fd := db.file.Fd()
+	var lockType int16
+	if exclusive {
+		lockType = syscall.F_WRLCK
+	} else {
+		lockType = syscall.F_RDLCK
+	}
 	for {
-		// If we're beyond our timeout then return an error.
-		// This can only occur after we've attempted a flock once.
-		if t.IsZero() {
-			t = time.Now()
-		} else if timeout > 0 && time.Since(t) > timeout {
-			return ErrTimeout
-		}
-		var lock syscall.Flock_t
-		lock.Start = 0
-		lock.Len = 0
-		lock.Pid = 0
-		lock.Whence = 0
-		lock.Pid = 0
-		if exclusive {
-			lock.Type = syscall.F_WRLCK
-		} else {
-			lock.Type = syscall.F_RDLCK
-		}
-		err := syscall.FcntlFlock(db.file.Fd(), syscall.F_SETLK, &lock)
+		// Attempt to obtain an exclusive lock.
+		lock := syscall.Flock_t{Type: lockType}
+		err := syscall.FcntlFlock(fd, syscall.F_SETLK, &lock)
 		if err == nil {
 			return nil
 		} else if err != syscall.EAGAIN {
 			return err
 		}
 
+		// If we timed out then return an error.
+		if timeout != 0 && time.Since(t) > timeout-flockRetryTimeout {
+			return ErrTimeout
+		}
+
 		// Wait for a bit and try again.
-		time.Sleep(50 * time.Millisecond)
+		time.Sleep(flockRetryTimeout)
 	}
 }
 
diff --git a/vendor/github.com/boltdb/bolt/bolt_windows.go b/vendor/go.etcd.io/bbolt/bolt_windows.go
similarity index 76%
rename from vendor/github.com/boltdb/bolt/bolt_windows.go
rename to vendor/go.etcd.io/bbolt/bolt_windows.go
index d538e6afd7..fca178bd29 100644
--- a/vendor/github.com/boltdb/bolt/bolt_windows.go
+++ b/vendor/go.etcd.io/bbolt/bolt_windows.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"fmt"
@@ -16,8 +16,6 @@ var (
 )
 
 const (
-	lockExt = ".lock"
-
 	// see https://msdn.microsoft.com/en-us/library/windows/desktop/aa365203(v=vs.85).aspx
 	flagLockExclusive       = 2
 	flagLockFailImmediately = 1
@@ -48,48 +46,47 @@ func fdatasync(db *DB) error {
 }
 
 // flock acquires an advisory lock on a file descriptor.
-func flock(db *DB, mode os.FileMode, exclusive bool, timeout time.Duration) error {
-	// Create a separate lock file on windows because a process
-	// cannot share an exclusive lock on the same file. This is
-	// needed during Tx.WriteTo().
-	f, err := os.OpenFile(db.path+lockExt, os.O_CREATE, mode)
-	if err != nil {
-		return err
-	}
-	db.lockfile = f
-
+func flock(db *DB, exclusive bool, timeout time.Duration) error {
 	var t time.Time
+	if timeout != 0 {
+		t = time.Now()
+	}
+	var flag uint32 = flagLockFailImmediately
+	if exclusive {
+		flag |= flagLockExclusive
+	}
 	for {
-		// If we're beyond our timeout then return an error.
-		// This can only occur after we've attempted a flock once.
-		if t.IsZero() {
-			t = time.Now()
-		} else if timeout > 0 && time.Since(t) > timeout {
-			return ErrTimeout
-		}
-
-		var flag uint32 = flagLockFailImmediately
-		if exclusive {
-			flag |= flagLockExclusive
-		}
+		// Fix for https://github.com/etcd-io/bbolt/issues/121. Use byte-range
+		// -1..0 as the lock on the database file.
+		var m1 uint32 = (1 << 32) - 1 // -1 in a uint32
+		err := lockFileEx(syscall.Handle(db.file.Fd()), flag, 0, 1, 0, &syscall.Overlapped{
+			Offset:     m1,
+			OffsetHigh: m1,
+		})
 
-		err := lockFileEx(syscall.Handle(db.lockfile.Fd()), flag, 0, 1, 0, &syscall.Overlapped{})
 		if err == nil {
 			return nil
 		} else if err != errLockViolation {
 			return err
 		}
 
+		// If we timed oumercit then return an error.
+		if timeout != 0 && time.Since(t) > timeout-flockRetryTimeout {
+			return ErrTimeout
+		}
+
 		// Wait for a bit and try again.
-		time.Sleep(50 * time.Millisecond)
+		time.Sleep(flockRetryTimeout)
 	}
 }
 
 // funlock releases an advisory lock on a file descriptor.
 func funlock(db *DB) error {
-	err := unlockFileEx(syscall.Handle(db.lockfile.Fd()), 0, 1, 0, &syscall.Overlapped{})
-	db.lockfile.Close()
-	os.Remove(db.path+lockExt)
+	var m1 uint32 = (1 << 32) - 1 // -1 in a uint32
+	err := unlockFileEx(syscall.Handle(db.file.Fd()), 0, 1, 0, &syscall.Overlapped{
+		Offset:     m1,
+		OffsetHigh: m1,
+	})
 	return err
 }
 
diff --git a/vendor/github.com/boltdb/bolt/boltsync_unix.go b/vendor/go.etcd.io/bbolt/boltsync_unix.go
similarity index 91%
rename from vendor/github.com/boltdb/bolt/boltsync_unix.go
rename to vendor/go.etcd.io/bbolt/boltsync_unix.go
index f50442523c..9587afefee 100644
--- a/vendor/github.com/boltdb/bolt/boltsync_unix.go
+++ b/vendor/go.etcd.io/bbolt/boltsync_unix.go
@@ -1,6 +1,6 @@
 // +build !windows,!plan9,!linux,!openbsd
 
-package bolt
+package bbolt
 
 // fdatasync flushes written data to a file descriptor.
 func fdatasync(db *DB) error {
diff --git a/vendor/github.com/boltdb/bolt/bucket.go b/vendor/go.etcd.io/bbolt/bucket.go
similarity index 99%
rename from vendor/github.com/boltdb/bolt/bucket.go
rename to vendor/go.etcd.io/bbolt/bucket.go
index 511ce72d33..84bfd4d6a2 100644
--- a/vendor/github.com/boltdb/bolt/bucket.go
+++ b/vendor/go.etcd.io/bbolt/bucket.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"bytes"
@@ -14,13 +14,6 @@ const (
 	MaxValueSize = (1 << 31) - 2
 )
 
-const (
-	maxUint = ^uint(0)
-	minUint = 0
-	maxInt  = int(^uint(0) >> 1)
-	minInt  = -maxInt - 1
-)
-
 const bucketHeaderSize = int(unsafe.Sizeof(bucket{}))
 
 const (
@@ -175,9 +168,8 @@ func (b *Bucket) CreateBucket(key []byte) (*Bucket, error) {
 	if bytes.Equal(key, k) {
 		if (flags & bucketLeafFlag) != 0 {
 			return nil, ErrBucketExists
-		} else {
-			return nil, ErrIncompatibleValue
 		}
+		return nil, ErrIncompatibleValue
 	}
 
 	// Create empty, inline bucket.
@@ -324,7 +316,12 @@ func (b *Bucket) Delete(key []byte) error {
 
 	// Move cursor to correct position.
 	c := b.Cursor()
-	_, _, flags := c.seek(key)
+	k, _, flags := c.seek(key)
+
+	// Return nil if the key doesn't exist.
+	if !bytes.Equal(key, k) {
+		return nil
+	}
 
 	// Return an error if there is already existing bucket value.
 	if (flags & bucketLeafFlag) != 0 {
diff --git a/vendor/github.com/boltdb/bolt/cursor.go b/vendor/go.etcd.io/bbolt/cursor.go
similarity index 99%
rename from vendor/github.com/boltdb/bolt/cursor.go
rename to vendor/go.etcd.io/bbolt/cursor.go
index 1be9f35e3e..3000aced6c 100644
--- a/vendor/github.com/boltdb/bolt/cursor.go
+++ b/vendor/go.etcd.io/bbolt/cursor.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"bytes"
@@ -157,12 +157,6 @@ func (c *Cursor) seek(seek []byte) (key []byte, value []byte, flags uint32) {
 	// Start from root page/node and traverse to correct page.
 	c.stack = c.stack[:0]
 	c.search(seek, c.bucket.root)
-	ref := &c.stack[len(c.stack)-1]
-
-	// If the cursor is pointing to the end of page/node then return nil.
-	if ref.index >= ref.count() {
-		return nil, nil, 0
-	}
 
 	// If this is a bucket then return a nil value.
 	return c.keyValue()
@@ -339,6 +333,8 @@ func (c *Cursor) nsearch(key []byte) {
 // keyValue returns the key and value of the current leaf element.
 func (c *Cursor) keyValue() ([]byte, []byte, uint32) {
 	ref := &c.stack[len(c.stack)-1]
+
+	// If the cursor is pointing to the end of page/node then return nil.
 	if ref.count() == 0 || ref.index >= ref.count() {
 		return nil, nil, 0
 	}
diff --git a/vendor/github.com/boltdb/bolt/db.go b/vendor/go.etcd.io/bbolt/db.go
similarity index 84%
rename from vendor/github.com/boltdb/bolt/db.go
rename to vendor/go.etcd.io/bbolt/db.go
index 1223493ca7..d91dcf813a 100644
--- a/vendor/github.com/boltdb/bolt/db.go
+++ b/vendor/go.etcd.io/bbolt/db.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"errors"
@@ -7,8 +7,7 @@ import (
 	"log"
 	"os"
 	"runtime"
-	"runtime/debug"
-	"strings"
+	"sort"
 	"sync"
 	"time"
 	"unsafe"
@@ -23,6 +22,8 @@ const version = 2
 // Represents a marker value to indicate that a file is a Bolt DB.
 const magic uint32 = 0xED0CDAED
 
+const pgidNoFreelist pgid = 0xffffffffffffffff
+
 // IgnoreNoSync specifies whether the NoSync field of a DB is ignored when
 // syncing changes to a file.  This is required as some operating systems,
 // such as OpenBSD, do not have a unified buffer cache (UBC) and writes
@@ -39,6 +40,9 @@ const (
 // default page size for db is set to the OS page size.
 var defaultPageSize = os.Getpagesize()
 
+// The time elapsed between consecutive file locking attempts.
+const flockRetryTimeout = 50 * time.Millisecond
+
 // DB represents a collection of buckets persisted to a file on disk.
 // All data access is performed through transactions which can be obtained through the DB.
 // All the functions on DB will return a ErrDatabaseNotOpen if accessed before Open() is called.
@@ -61,6 +65,11 @@ type DB struct {
 	// THIS IS UNSAFE. PLEASE USE WITH CAUTION.
 	NoSync bool
 
+	// When true, skips syncing freelist to disk. This improves the database
+	// write performance under normal operation, but requires a full database
+	// re-sync during recovery.
+	NoFreelistSync bool
+
 	// When true, skips the truncate call when growing the database.
 	// Setting this to true is only safe on non-ext3/ext4 systems.
 	// Skipping truncation avoids preallocation of hard drive space and
@@ -96,8 +105,7 @@ type DB struct {
 
 	path     string
 	file     *os.File
-	lockfile *os.File // windows only
-	dataref  []byte   // mmap'ed readonly, write throws SEGV
+	dataref  []byte // mmap'ed readonly, write throws SEGV
 	data     *[maxMapSize]byte
 	datasz   int
 	filesz   int // current on disk file size
@@ -107,9 +115,11 @@ type DB struct {
 	opened   bool
 	rwtx     *Tx
 	txs      []*Tx
-	freelist *freelist
 	stats    Stats
 
+	freelist     *freelist
+	freelistLoad sync.Once
+
 	pagePool sync.Pool
 
 	batchMu sync.Mutex
@@ -148,14 +158,17 @@ func (db *DB) String() string {
 // If the file does not exist then it will be created automatically.
 // Passing in nil options will cause Bolt to open the database with the default options.
 func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
-	var db = &DB{opened: true}
-
+	db := &DB{
+		opened: true,
+	}
 	// Set default options if no options are provided.
 	if options == nil {
 		options = DefaultOptions
 	}
+	db.NoSync = options.NoSync
 	db.NoGrowSync = options.NoGrowSync
 	db.MmapFlags = options.MmapFlags
+	db.NoFreelistSync = options.NoFreelistSync
 
 	// Set default values for later DB operations.
 	db.MaxBatchSize = DefaultMaxBatchSize
@@ -183,7 +196,7 @@ func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
 	// if !options.ReadOnly.
 	// The database file is locked using the shared lock (more than one process may
 	// hold a lock at the same time) otherwise (options.ReadOnly is set).
-	if err := flock(db, mode, !db.readOnly, options.Timeout); err != nil {
+	if err := flock(db, !db.readOnly, options.Timeout); err != nil {
 		_ = db.close()
 		return nil, err
 	}
@@ -191,31 +204,41 @@ func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
 	// Default values for test hooks
 	db.ops.writeAt = db.file.WriteAt
 
+	if db.pageSize = options.PageSize; db.pageSize == 0 {
+		// Set the default page size to the OS page size.
+		db.pageSize = defaultPageSize
+	}
+
 	// Initialize the database if it doesn't exist.
 	if info, err := db.file.Stat(); err != nil {
+		_ = db.close()
 		return nil, err
 	} else if info.Size() == 0 {
 		// Initialize new files with meta pages.
 		if err := db.init(); err != nil {
+			// clean up file descriptor on initialization fail
+			_ = db.close()
 			return nil, err
 		}
 	} else {
 		// Read the first meta page to determine the page size.
 		var buf [0x1000]byte
-		if _, err := db.file.ReadAt(buf[:], 0); err == nil {
-			m := db.pageInBuffer(buf[:], 0).meta()
-			if err := m.validate(); err != nil {
-				// If we can't read the page size, we can assume it's the same
-				// as the OS -- since that's how the page size was chosen in the
-				// first place.
-				//
-				// If the first page is invalid and this OS uses a different
-				// page size than what the database was created with then we
-				// are out of luck and cannot access the database.
-				db.pageSize = os.Getpagesize()
-			} else {
+		// If we can't read the page size, but can read a page, assume
+		// it's the same as the OS or one given -- since that's how the
+		// page size was chosen in the first place.
+		//
+		// If the first page is invalid and this OS uses a different
+		// page size than what the database was created with then we
+		// are out of luck and cannot access the database.
+		//
+		// TODO: scan for next page
+		if bw, err := db.file.ReadAt(buf[:], 0); err == nil && bw == len(buf) {
+			if m := db.pageInBuffer(buf[:], 0).meta(); m.validate() == nil {
 				db.pageSize = int(m.pageSize)
 			}
+		} else {
+			_ = db.close()
+			return nil, ErrInvalid
 		}
 	}
 
@@ -232,14 +255,50 @@ func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
 		return nil, err
 	}
 
-	// Read in the freelist.
-	db.freelist = newFreelist()
-	db.freelist.read(db.page(db.meta().freelist))
+	if db.readOnly {
+		return db, nil
+	}
+
+	db.loadFreelist()
+
+	// Flush freelist when transitioning from no sync to sync so
+	// NoFreelistSync unaware boltdb can open the db later.
+	if !db.NoFreelistSync && !db.hasSyncedFreelist() {
+		tx, err := db.Begin(true)
+		if tx != nil {
+			err = tx.Commit()
+		}
+		if err != nil {
+			_ = db.close()
+			return nil, err
+		}
+	}
 
 	// Mark the database as opened and return.
 	return db, nil
 }
 
+// loadFreelist reads the freelist if it is synced, or reconstructs it
+// by scanning the DB if it is not synced. It assumes there are no
+// concurrent accesses being made to the freelist.
+func (db *DB) loadFreelist() {
+	db.freelistLoad.Do(func() {
+		db.freelist = newFreelist()
+		if !db.hasSyncedFreelist() {
+			// Reconstruct free list by scanning the DB.
+			db.freelist.readIDs(db.freepages())
+		} else {
+			// Read free list from freelist page.
+			db.freelist.read(db.page(db.meta().freelist))
+		}
+		db.stats.FreePageN = len(db.freelist.ids)
+	})
+}
+
+func (db *DB) hasSyncedFreelist() bool {
+	return db.meta().freelist != pgidNoFreelist
+}
+
 // mmap opens the underlying memory-mapped file and initializes the meta references.
 // minsz is the minimum size that the new mmap can be.
 func (db *DB) mmap(minsz int) error {
@@ -341,9 +400,6 @@ func (db *DB) mmapSize(size int) (int, error) {
 
 // init creates a new database file and initializes its meta pages.
 func (db *DB) init() error {
-	// Set the page size to the OS page size.
-	db.pageSize = os.Getpagesize()
-
 	// Create two meta pages on a buffer.
 	buf := make([]byte, db.pageSize*4)
 	for i := 0; i < 2; i++ {
@@ -387,7 +443,8 @@ func (db *DB) init() error {
 }
 
 // Close releases all database resources.
-// All transactions must be closed before closing the database.
+// It will block waiting for any open transactions to finish
+// before closing the database and returning.
 func (db *DB) Close() error {
 	db.rwlock.Lock()
 	defer db.rwlock.Unlock()
@@ -395,8 +452,8 @@ func (db *DB) Close() error {
 	db.metalock.Lock()
 	defer db.metalock.Unlock()
 
-	db.mmaplock.RLock()
-	defer db.mmaplock.RUnlock()
+	db.mmaplock.Lock()
+	defer db.mmaplock.Unlock()
 
 	return db.close()
 }
@@ -526,21 +583,36 @@ func (db *DB) beginRWTx() (*Tx, error) {
 	t := &Tx{writable: true}
 	t.init(db)
 	db.rwtx = t
+	db.freePages()
+	return t, nil
+}
 
-	// Free any pages associated with closed read-only transactions.
-	var minid txid = 0xFFFFFFFFFFFFFFFF
-	for _, t := range db.txs {
-		if t.meta.txid < minid {
-			minid = t.meta.txid
-		}
+// freePages releases any pages associated with closed read-only transactions.
+func (db *DB) freePages() {
+	// Free all pending pages prior to earliest open transaction.
+	sort.Sort(txsById(db.txs))
+	minid := txid(0xFFFFFFFFFFFFFFFF)
+	if len(db.txs) > 0 {
+		minid = db.txs[0].meta.txid
 	}
 	if minid > 0 {
 		db.freelist.release(minid - 1)
 	}
-
-	return t, nil
+	// Release unused txid extents.
+	for _, t := range db.txs {
+		db.freelist.releaseRange(minid, t.meta.txid-1)
+		minid = t.meta.txid + 1
+	}
+	db.freelist.releaseRange(minid, txid(0xFFFFFFFFFFFFFFFF))
+	// Any page both allocated and freed in an extent is safe to release.
 }
 
+type txsById []*Tx
+
+func (t txsById) Len() int           { return len(t) }
+func (t txsById) Swap(i, j int)      { t[i], t[j] = t[j], t[i] }
+func (t txsById) Less(i, j int) bool { return t[i].meta.txid < t[j].meta.txid }
+
 // removeTx removes a transaction from the database.
 func (db *DB) removeTx(tx *Tx) {
 	// Release the read lock on the mmap.
@@ -552,7 +624,10 @@ func (db *DB) removeTx(tx *Tx) {
 	// Remove the transaction.
 	for i, t := range db.txs {
 		if t == tx {
-			db.txs = append(db.txs[:i], db.txs[i+1:]...)
+			last := len(db.txs) - 1
+			db.txs[i] = db.txs[last]
+			db.txs[last] = nil
+			db.txs = db.txs[:last]
 			break
 		}
 	}
@@ -630,11 +705,7 @@ func (db *DB) View(fn func(*Tx) error) error {
 		return err
 	}
 
-	if err := t.Rollback(); err != nil {
-		return err
-	}
-
-	return nil
+	return t.Rollback()
 }
 
 // Batch calls fn as part of a batch. It behaves similar to Update,
@@ -734,9 +805,7 @@ retry:
 
 		// pass success, or bolt internal errors, to all callers
 		for _, c := range b.calls {
-			if c.err != nil {
-				c.err <- err
-			}
+			c.err <- err
 		}
 		break retry
 	}
@@ -823,7 +892,7 @@ func (db *DB) meta() *meta {
 }
 
 // allocate returns a contiguous block of memory starting at a given page.
-func (db *DB) allocate(count int) (*page, error) {
+func (db *DB) allocate(txid txid, count int) (*page, error) {
 	// Allocate a temporary buffer for the page.
 	var buf []byte
 	if count == 1 {
@@ -835,7 +904,7 @@ func (db *DB) allocate(count int) (*page, error) {
 	p.overflow = uint32(count - 1)
 
 	// Use pages from the freelist if they are available.
-	if p.id = db.freelist.allocate(count); p.id != 0 {
+	if p.id = db.freelist.allocate(txid, count); p.id != 0 {
 		return p, nil
 	}
 
@@ -890,6 +959,38 @@ func (db *DB) IsReadOnly() bool {
 	return db.readOnly
 }
 
+func (db *DB) freepages() []pgid {
+	tx, err := db.beginTx()
+	defer func() {
+		err = tx.Rollback()
+		if err != nil {
+			panic("freepages: failed to rollback tx")
+		}
+	}()
+	if err != nil {
+		panic("freepages: failed to open read only tx")
+	}
+
+	reachable := make(map[pgid]*page)
+	nofreed := make(map[pgid]bool)
+	ech := make(chan error)
+	go func() {
+		for e := range ech {
+			panic(fmt.Sprintf("freepages: failed to get all reachable pages (%v)", e))
+		}
+	}()
+	tx.checkBucket(&tx.root, reachable, nofreed, ech)
+	close(ech)
+
+	var fids []pgid
+	for i := pgid(2); i < db.meta().pgid; i++ {
+		if _, ok := reachable[i]; !ok {
+			fids = append(fids, i)
+		}
+	}
+	return fids
+}
+
 // Options represents the options that can be set when opening a database.
 type Options struct {
 	// Timeout is the amount of time to wait to obtain a file lock.
@@ -900,6 +1001,10 @@ type Options struct {
 	// Sets the DB.NoGrowSync flag before memory mapping the file.
 	NoGrowSync bool
 
+	// Do not sync freelist to disk. This improves the database write performance
+	// under normal operation, but requires a full database re-sync during recovery.
+	NoFreelistSync bool
+
 	// Open database in read-only mode. Uses flock(..., LOCK_SH |LOCK_NB) to
 	// grab a shared lock (UNIX).
 	ReadOnly bool
@@ -916,6 +1021,14 @@ type Options struct {
 	// If initialMmapSize is smaller than the previous database size,
 	// it takes no effect.
 	InitialMmapSize int
+
+	// PageSize overrides the default OS page size.
+	PageSize int
+
+	// NoSync sets the initial value of DB.NoSync. Normally this can just be
+	// set directly on the DB itself when returned from Open(), but this option
+	// is useful in APIs which expose Options but not the underlying DB.
+	NoSync bool
 }
 
 // DefaultOptions represent the options used if nil options are passed into Open().
@@ -952,15 +1065,11 @@ func (s *Stats) Sub(other *Stats) Stats {
 	diff.PendingPageN = s.PendingPageN
 	diff.FreeAlloc = s.FreeAlloc
 	diff.FreelistInuse = s.FreelistInuse
-	diff.TxN = other.TxN - s.TxN
+	diff.TxN = s.TxN - other.TxN
 	diff.TxStats = s.TxStats.Sub(&other.TxStats)
 	return diff
 }
 
-func (s *Stats) add(other *Stats) {
-	s.TxStats.add(&other.TxStats)
-}
-
 type Info struct {
 	Data     uintptr
 	PageSize int
@@ -999,7 +1108,8 @@ func (m *meta) copy(dest *meta) {
 func (m *meta) write(p *page) {
 	if m.root.root >= m.pgid {
 		panic(fmt.Sprintf("root bucket pgid (%d) above high water mark (%d)", m.root.root, m.pgid))
-	} else if m.freelist >= m.pgid {
+	} else if m.freelist >= m.pgid && m.freelist != pgidNoFreelist {
+		// TODO: reject pgidNoFreeList if !NoFreelistSync
 		panic(fmt.Sprintf("freelist pgid (%d) above high water mark (%d)", m.freelist, m.pgid))
 	}
 
@@ -1026,11 +1136,3 @@ func _assert(condition bool, msg string, v ...interface{}) {
 		panic(fmt.Sprintf("assertion failed: "+msg, v...))
 	}
 }
-
-func warn(v ...interface{})              { fmt.Fprintln(os.Stderr, v...) }
-func warnf(msg string, v ...interface{}) { fmt.Fprintf(os.Stderr, msg+"\n", v...) }
-
-func printstack() {
-	stack := strings.Join(strings.Split(string(debug.Stack()), "\n")[2:], "\n")
-	fmt.Fprintln(os.Stderr, stack)
-}
diff --git a/vendor/github.com/boltdb/bolt/doc.go b/vendor/go.etcd.io/bbolt/doc.go
similarity index 94%
rename from vendor/github.com/boltdb/bolt/doc.go
rename to vendor/go.etcd.io/bbolt/doc.go
index cc937845db..95f25f01c6 100644
--- a/vendor/github.com/boltdb/bolt/doc.go
+++ b/vendor/go.etcd.io/bbolt/doc.go
@@ -1,5 +1,5 @@
 /*
-Package bolt implements a low-level key/value store in pure Go. It supports
+package bbolt implements a low-level key/value store in pure Go. It supports
 fully serializable transactions, ACID semantics, and lock-free MVCC with
 multiple readers and a single writer. Bolt can be used for projects that
 want a simple data store without the need to add large dependencies such as
@@ -41,4 +41,4 @@ point to different data or can point to invalid memory which will cause a panic.
 
 
 */
-package bolt
+package bbolt
diff --git a/vendor/github.com/boltdb/bolt/errors.go b/vendor/go.etcd.io/bbolt/errors.go
similarity index 99%
rename from vendor/github.com/boltdb/bolt/errors.go
rename to vendor/go.etcd.io/bbolt/errors.go
index a3620a3ebb..48758ca577 100644
--- a/vendor/github.com/boltdb/bolt/errors.go
+++ b/vendor/go.etcd.io/bbolt/errors.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import "errors"
 
diff --git a/vendor/github.com/boltdb/bolt/freelist.go b/vendor/go.etcd.io/bbolt/freelist.go
similarity index 57%
rename from vendor/github.com/boltdb/bolt/freelist.go
rename to vendor/go.etcd.io/bbolt/freelist.go
index d32f6cd937..e4bcb2dcf9 100644
--- a/vendor/github.com/boltdb/bolt/freelist.go
+++ b/vendor/go.etcd.io/bbolt/freelist.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"fmt"
@@ -6,25 +6,40 @@ import (
 	"unsafe"
 )
 
+// txPending holds a list of pgids and corresponding allocation txns
+// that are pending to be freed.
+type txPending struct {
+	ids              []pgid
+	alloctx          []txid // txids allocating the ids
+	lastReleaseBegin txid   // beginning txid of last matching releaseRange
+}
+
 // freelist represents a list of all pages that are available for allocation.
 // It also tracks pages that have been freed but are still in use by open transactions.
 type freelist struct {
-	ids     []pgid          // all free and available free page ids.
-	pending map[txid][]pgid // mapping of soon-to-be free page ids by tx.
-	cache   map[pgid]bool   // fast lookup of all free and pending page ids.
+	ids     []pgid              // all free and available free page ids.
+	allocs  map[pgid]txid       // mapping of txid that allocated a pgid.
+	pending map[txid]*txPending // mapping of soon-to-be free page ids by tx.
+	cache   map[pgid]bool       // fast lookup of all free and pending page ids.
 }
 
 // newFreelist returns an empty, initialized freelist.
 func newFreelist() *freelist {
 	return &freelist{
-		pending: make(map[txid][]pgid),
+		allocs:  make(map[pgid]txid),
+		pending: make(map[txid]*txPending),
 		cache:   make(map[pgid]bool),
 	}
 }
 
 // size returns the size of the page after serialization.
 func (f *freelist) size() int {
-	return pageHeaderSize + (int(unsafe.Sizeof(pgid(0))) * f.count())
+	n := f.count()
+	if n >= 0xFFFF {
+		// The first element will be used to store the count. See freelist.write.
+		n++
+	}
+	return pageHeaderSize + (int(unsafe.Sizeof(pgid(0))) * n)
 }
 
 // count returns count of pages on the freelist
@@ -40,27 +55,26 @@ func (f *freelist) free_count() int {
 // pending_count returns count of pending pages
 func (f *freelist) pending_count() int {
 	var count int
-	for _, list := range f.pending {
-		count += len(list)
+	for _, txp := range f.pending {
+		count += len(txp.ids)
 	}
 	return count
 }
 
-// all returns a list of all free ids and all pending ids in one sorted list.
-func (f *freelist) all() []pgid {
-	m := make(pgids, 0)
-
-	for _, list := range f.pending {
-		m = append(m, list...)
+// copyall copies into dst a list of all free ids and all pending ids in one sorted list.
+// f.count returns the minimum length required for dst.
+func (f *freelist) copyall(dst []pgid) {
+	m := make(pgids, 0, f.pending_count())
+	for _, txp := range f.pending {
+		m = append(m, txp.ids...)
 	}
-
 	sort.Sort(m)
-	return pgids(f.ids).merge(m)
+	mergepgids(dst, f.ids, m)
 }
 
 // allocate returns the starting page id of a contiguous list of pages of a given size.
 // If a contiguous block cannot be found then 0 is returned.
-func (f *freelist) allocate(n int) pgid {
+func (f *freelist) allocate(txid txid, n int) pgid {
 	if len(f.ids) == 0 {
 		return 0
 	}
@@ -93,7 +107,7 @@ func (f *freelist) allocate(n int) pgid {
 			for i := pgid(0); i < pgid(n); i++ {
 				delete(f.cache, initial+i)
 			}
-
+			f.allocs[initial] = txid
 			return initial
 		}
 
@@ -110,28 +124,73 @@ func (f *freelist) free(txid txid, p *page) {
 	}
 
 	// Free page and all its overflow pages.
-	var ids = f.pending[txid]
+	txp := f.pending[txid]
+	if txp == nil {
+		txp = &txPending{}
+		f.pending[txid] = txp
+	}
+	allocTxid, ok := f.allocs[p.id]
+	if ok {
+		delete(f.allocs, p.id)
+	} else if (p.flags & freelistPageFlag) != 0 {
+		// Freelist is always allocated by prior tx.
+		allocTxid = txid - 1
+	}
+
 	for id := p.id; id <= p.id+pgid(p.overflow); id++ {
 		// Verify that page is not already free.
 		if f.cache[id] {
 			panic(fmt.Sprintf("page %d already freed", id))
 		}
-
 		// Add to the freelist and cache.
-		ids = append(ids, id)
+		txp.ids = append(txp.ids, id)
+		txp.alloctx = append(txp.alloctx, allocTxid)
 		f.cache[id] = true
 	}
-	f.pending[txid] = ids
 }
 
 // release moves all page ids for a transaction id (or older) to the freelist.
 func (f *freelist) release(txid txid) {
 	m := make(pgids, 0)
-	for tid, ids := range f.pending {
+	for tid, txp := range f.pending {
 		if tid <= txid {
 			// Move transaction's pending pages to the available freelist.
 			// Don't remove from the cache since the page is still free.
-			m = append(m, ids...)
+			m = append(m, txp.ids...)
+			delete(f.pending, tid)
+		}
+	}
+	sort.Sort(m)
+	f.ids = pgids(f.ids).merge(m)
+}
+
+// releaseRange moves pending pages allocated within an extent [begin,end] to the free list.
+func (f *freelist) releaseRange(begin, end txid) {
+	if begin > end {
+		return
+	}
+	var m pgids
+	for tid, txp := range f.pending {
+		if tid < begin || tid > end {
+			continue
+		}
+		// Don't recompute freed pages if ranges haven't updated.
+		if txp.lastReleaseBegin == begin {
+			continue
+		}
+		for i := 0; i < len(txp.ids); i++ {
+			if atx := txp.alloctx[i]; atx < begin || atx > end {
+				continue
+			}
+			m = append(m, txp.ids[i])
+			txp.ids[i] = txp.ids[len(txp.ids)-1]
+			txp.ids = txp.ids[:len(txp.ids)-1]
+			txp.alloctx[i] = txp.alloctx[len(txp.alloctx)-1]
+			txp.alloctx = txp.alloctx[:len(txp.alloctx)-1]
+			i--
+		}
+		txp.lastReleaseBegin = begin
+		if len(txp.ids) == 0 {
 			delete(f.pending, tid)
 		}
 	}
@@ -142,12 +201,29 @@ func (f *freelist) release(txid txid) {
 // rollback removes the pages from a given pending tx.
 func (f *freelist) rollback(txid txid) {
 	// Remove page ids from cache.
-	for _, id := range f.pending[txid] {
-		delete(f.cache, id)
+	txp := f.pending[txid]
+	if txp == nil {
+		return
 	}
-
-	// Remove pages from pending list.
+	var m pgids
+	for i, pgid := range txp.ids {
+		delete(f.cache, pgid)
+		tx := txp.alloctx[i]
+		if tx == 0 {
+			continue
+		}
+		if tx != txid {
+			// Pending free aborted; restore page back to alloc list.
+			f.allocs[pgid] = tx
+		} else {
+			// Freed page was allocated by this txn; OK to throw away.
+			m = append(m, pgid)
+		}
+	}
+	// Remove pages from pending list and mark as free if allocated by txid.
 	delete(f.pending, txid)
+	sort.Sort(m)
+	f.ids = pgids(f.ids).merge(m)
 }
 
 // freed returns whether a given page is in the free list.
@@ -157,6 +233,9 @@ func (f *freelist) freed(pgid pgid) bool {
 
 // read initializes the freelist from a freelist page.
 func (f *freelist) read(p *page) {
+	if (p.flags & freelistPageFlag) == 0 {
+		panic(fmt.Sprintf("invalid freelist page: %d, page type is %s", p.id, p.typ()))
+	}
 	// If the page.count is at the max uint16 value (64k) then it's considered
 	// an overflow and the size of the freelist is stored as the first element.
 	idx, count := 0, int(p.count)
@@ -169,7 +248,7 @@ func (f *freelist) read(p *page) {
 	if count == 0 {
 		f.ids = nil
 	} else {
-		ids := ((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[idx:count]
+		ids := ((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[idx : idx+count]
 		f.ids = make([]pgid, len(ids))
 		copy(f.ids, ids)
 
@@ -181,27 +260,33 @@ func (f *freelist) read(p *page) {
 	f.reindex()
 }
 
+// read initializes the freelist from a given list of ids.
+func (f *freelist) readIDs(ids []pgid) {
+	f.ids = ids
+	f.reindex()
+}
+
 // write writes the page ids onto a freelist page. All free and pending ids are
 // saved to disk since in the event of a program crash, all pending ids will
 // become free.
 func (f *freelist) write(p *page) error {
 	// Combine the old free pgids and pgids waiting on an open transaction.
-	ids := f.all()
 
 	// Update the header flag.
 	p.flags |= freelistPageFlag
 
 	// The page.count can only hold up to 64k elements so if we overflow that
 	// number then we handle it by putting the size in the first element.
-	if len(ids) == 0 {
-		p.count = uint16(len(ids))
-	} else if len(ids) < 0xFFFF {
-		p.count = uint16(len(ids))
-		copy(((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[:], ids)
+	lenids := f.count()
+	if lenids == 0 {
+		p.count = uint16(lenids)
+	} else if lenids < 0xFFFF {
+		p.count = uint16(lenids)
+		f.copyall(((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[:])
 	} else {
 		p.count = 0xFFFF
-		((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[0] = pgid(len(ids))
-		copy(((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[1:], ids)
+		((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[0] = pgid(lenids)
+		f.copyall(((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[1:])
 	}
 
 	return nil
@@ -213,8 +298,8 @@ func (f *freelist) reload(p *page) {
 
 	// Build a cache of only pending pages.
 	pcache := make(map[pgid]bool)
-	for _, pendingIDs := range f.pending {
-		for _, pendingID := range pendingIDs {
+	for _, txp := range f.pending {
+		for _, pendingID := range txp.ids {
 			pcache[pendingID] = true
 		}
 	}
@@ -240,8 +325,8 @@ func (f *freelist) reindex() {
 	for _, id := range f.ids {
 		f.cache[id] = true
 	}
-	for _, pendingIDs := range f.pending {
-		for _, pendingID := range pendingIDs {
+	for _, txp := range f.pending {
+		for _, pendingID := range txp.ids {
 			f.cache[pendingID] = true
 		}
 	}
diff --git a/vendor/github.com/boltdb/bolt/node.go b/vendor/go.etcd.io/bbolt/node.go
similarity index 99%
rename from vendor/github.com/boltdb/bolt/node.go
rename to vendor/go.etcd.io/bbolt/node.go
index 159318b229..6c3fa553ea 100644
--- a/vendor/github.com/boltdb/bolt/node.go
+++ b/vendor/go.etcd.io/bbolt/node.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"bytes"
@@ -365,7 +365,7 @@ func (n *node) spill() error {
 		}
 
 		// Allocate contiguous space for the node.
-		p, err := tx.allocate((node.size() / tx.db.pageSize) + 1)
+		p, err := tx.allocate((node.size() + tx.db.pageSize - 1) / tx.db.pageSize)
 		if err != nil {
 			return err
 		}
diff --git a/vendor/github.com/boltdb/bolt/page.go b/vendor/go.etcd.io/bbolt/page.go
similarity index 88%
rename from vendor/github.com/boltdb/bolt/page.go
rename to vendor/go.etcd.io/bbolt/page.go
index 7651a6bf7d..bca9615f0f 100644
--- a/vendor/github.com/boltdb/bolt/page.go
+++ b/vendor/go.etcd.io/bbolt/page.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"fmt"
@@ -145,12 +145,33 @@ func (a pgids) merge(b pgids) pgids {
 	// Return the opposite slice if one is nil.
 	if len(a) == 0 {
 		return b
-	} else if len(b) == 0 {
+	}
+	if len(b) == 0 {
 		return a
 	}
+	merged := make(pgids, len(a)+len(b))
+	mergepgids(merged, a, b)
+	return merged
+}
+
+// mergepgids copies the sorted union of a and b into dst.
+// If dst is too small, it panics.
+func mergepgids(dst, a, b pgids) {
+	if len(dst) < len(a)+len(b) {
+		panic(fmt.Errorf("mergepgids bad len %d < %d + %d", len(dst), len(a), len(b)))
+	}
+	// Copy in the opposite slice if one is nil.
+	if len(a) == 0 {
+		copy(dst, b)
+		return
+	}
+	if len(b) == 0 {
+		copy(dst, a)
+		return
+	}
 
-	// Create a list to hold all elements from both lists.
-	merged := make(pgids, 0, len(a)+len(b))
+	// Merged will hold all elements from both lists.
+	merged := dst[:0]
 
 	// Assign lead to the slice with a lower starting value, follow to the higher value.
 	lead, follow := a, b
@@ -172,7 +193,5 @@ func (a pgids) merge(b pgids) pgids {
 	}
 
 	// Append what's left in follow.
-	merged = append(merged, follow...)
-
-	return merged
+	_ = append(merged, follow...)
 }
diff --git a/vendor/github.com/boltdb/bolt/tx.go b/vendor/go.etcd.io/bbolt/tx.go
similarity index 93%
rename from vendor/github.com/boltdb/bolt/tx.go
rename to vendor/go.etcd.io/bbolt/tx.go
index 1cfb4cde85..f508641427 100644
--- a/vendor/github.com/boltdb/bolt/tx.go
+++ b/vendor/go.etcd.io/bbolt/tx.go
@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"fmt"
@@ -126,10 +126,7 @@ func (tx *Tx) DeleteBucket(name []byte) error {
 // the error is returned to the caller.
 func (tx *Tx) ForEach(fn func(name []byte, b *Bucket) error) error {
 	return tx.root.ForEach(func(k, v []byte) error {
-		if err := fn(k, tx.root.Bucket(k)); err != nil {
-			return err
-		}
-		return nil
+		return fn(k, tx.root.Bucket(k))
 	})
 }
 
@@ -169,28 +166,18 @@ func (tx *Tx) Commit() error {
 	// Free the old root bucket.
 	tx.meta.root.root = tx.root.root
 
-	opgid := tx.meta.pgid
-
-	// Free the freelist and allocate new pages for it. This will overestimate
-	// the size of the freelist but not underestimate the size (which would be bad).
-	tx.db.freelist.free(tx.meta.txid, tx.db.page(tx.meta.freelist))
-	p, err := tx.allocate((tx.db.freelist.size() / tx.db.pageSize) + 1)
-	if err != nil {
-		tx.rollback()
-		return err
-	}
-	if err := tx.db.freelist.write(p); err != nil {
-		tx.rollback()
-		return err
+	// Free the old freelist because commit writes out a fresh freelist.
+	if tx.meta.freelist != pgidNoFreelist {
+		tx.db.freelist.free(tx.meta.txid, tx.db.page(tx.meta.freelist))
 	}
-	tx.meta.freelist = p.id
 
-	// If the high water mark has moved up then attempt to grow the database.
-	if tx.meta.pgid > opgid {
-		if err := tx.db.grow(int(tx.meta.pgid+1) * tx.db.pageSize); err != nil {
-			tx.rollback()
+	if !tx.db.NoFreelistSync {
+		err := tx.commitFreelist()
+		if err != nil {
 			return err
 		}
+	} else {
+		tx.meta.freelist = pgidNoFreelist
 	}
 
 	// Write dirty pages to disk.
@@ -235,6 +222,31 @@ func (tx *Tx) Commit() error {
 	return nil
 }
 
+func (tx *Tx) commitFreelist() error {
+	// Allocate new pages for the new free list. This will overestimate
+	// the size of the freelist but not underestimate the size (which would be bad).
+	opgid := tx.meta.pgid
+	p, err := tx.allocate((tx.db.freelist.size() / tx.db.pageSize) + 1)
+	if err != nil {
+		tx.rollback()
+		return err
+	}
+	if err := tx.db.freelist.write(p); err != nil {
+		tx.rollback()
+		return err
+	}
+	tx.meta.freelist = p.id
+	// If the high water mark has moved up then attempt to grow the database.
+	if tx.meta.pgid > opgid {
+		if err := tx.db.grow(int(tx.meta.pgid+1) * tx.db.pageSize); err != nil {
+			tx.rollback()
+			return err
+		}
+	}
+
+	return nil
+}
+
 // Rollback closes the transaction and ignores all previous updates. Read-only
 // transactions must be rolled back and not committed.
 func (tx *Tx) Rollback() error {
@@ -291,7 +303,9 @@ func (tx *Tx) close() {
 }
 
 // Copy writes the entire database to a writer.
-// This function exists for backwards compatibility. Use WriteTo() instead.
+// This function exists for backwards compatibility.
+//
+// Deprecated; Use WriteTo() instead.
 func (tx *Tx) Copy(w io.Writer) error {
 	_, err := tx.WriteTo(w)
 	return err
@@ -305,7 +319,11 @@ func (tx *Tx) WriteTo(w io.Writer) (n int64, err error) {
 	if err != nil {
 		return 0, err
 	}
-	defer func() { _ = f.Close() }()
+	defer func() {
+		if cerr := f.Close(); err == nil {
+			err = cerr
+		}
+	}()
 
 	// Generate a meta page. We use the same page data for both meta pages.
 	buf := make([]byte, tx.db.pageSize)
@@ -333,7 +351,7 @@ func (tx *Tx) WriteTo(w io.Writer) (n int64, err error) {
 	}
 
 	// Move past the meta pages in the file.
-	if _, err := f.Seek(int64(tx.db.pageSize*2), os.SEEK_SET); err != nil {
+	if _, err := f.Seek(int64(tx.db.pageSize*2), io.SeekStart); err != nil {
 		return n, fmt.Errorf("seek: %s", err)
 	}
 
@@ -344,7 +362,7 @@ func (tx *Tx) WriteTo(w io.Writer) (n int64, err error) {
 		return n, err
 	}
 
-	return n, f.Close()
+	return n, nil
 }
 
 // CopyFile copies the entire database to file at the given path.
@@ -379,9 +397,14 @@ func (tx *Tx) Check() <-chan error {
 }
 
 func (tx *Tx) check(ch chan error) {
+	// Force loading free list if opened in ReadOnly mode.
+	tx.db.loadFreelist()
+
 	// Check if any pages are double freed.
 	freed := make(map[pgid]bool)
-	for _, id := range tx.db.freelist.all() {
+	all := make([]pgid, tx.db.freelist.count())
+	tx.db.freelist.copyall(all)
+	for _, id := range all {
 		if freed[id] {
 			ch <- fmt.Errorf("page %d: already freed", id)
 		}
@@ -392,8 +415,10 @@ func (tx *Tx) check(ch chan error) {
 	reachable := make(map[pgid]*page)
 	reachable[0] = tx.page(0) // meta0
 	reachable[1] = tx.page(1) // meta1
-	for i := uint32(0); i <= tx.page(tx.meta.freelist).overflow; i++ {
-		reachable[tx.meta.freelist+pgid(i)] = tx.page(tx.meta.freelist)
+	if tx.meta.freelist != pgidNoFreelist {
+		for i := uint32(0); i <= tx.page(tx.meta.freelist).overflow; i++ {
+			reachable[tx.meta.freelist+pgid(i)] = tx.page(tx.meta.freelist)
+		}
 	}
 
 	// Recursively check buckets.
@@ -451,7 +476,7 @@ func (tx *Tx) checkBucket(b *Bucket, reachable map[pgid]*page, freed map[pgid]bo
 
 // allocate returns a contiguous block of memory starting at a given page.
 func (tx *Tx) allocate(count int) (*page, error) {
-	p, err := tx.db.allocate(count)
+	p, err := tx.db.allocate(tx.meta.txid, count)
 	if err != nil {
 		return nil, err
 	}
@@ -460,7 +485,7 @@ func (tx *Tx) allocate(count int) (*page, error) {
 	tx.pages[p.id] = p
 
 	// Update statistics.
-	tx.stats.PageCount++
+	tx.stats.PageCount += count
 	tx.stats.PageAlloc += count * tx.db.pageSize
 
 	return p, nil