From 1817c8760046b32a43e7af3ec7106ec92a074321 Mon Sep 17 00:00:00 2001 From: Lucas Capistrant Date: Wed, 4 Sep 2019 14:00:09 -0500 Subject: [PATCH] Add druid.segmentCache.numBootstrapThreads back to the docs --- docs/configuration/index.md | 1 + 1 file changed, 1 insertion(+) diff --git a/docs/configuration/index.md b/docs/configuration/index.md index 520a83b1d53c..7d8aaaa1f4d1 100644 --- a/docs/configuration/index.md +++ b/docs/configuration/index.md @@ -1207,6 +1207,7 @@ These Historical configurations can be defined in the `historical/runtime.proper |`druid.segmentCache.infoDir`|Historical processes keep track of the segments they are serving so that when the process is restarted they can reload the same segments without waiting for the Coordinator to reassign. This path defines where this metadata is kept. Directory will be created if needed.|${first_location}/info_dir| |`druid.segmentCache.announceIntervalMillis`|How frequently to announce segments while segments are loading from cache. Set this value to zero to wait for all segments to be loaded before announcing.|5000 (5 seconds)| |`druid.segmentCache.numLoadingThreads`|How many segments to drop or load concurrently from deep storage. Note that the work of loading segments involves downloading segments from deep storage, decompressing them and loading them to a memory mapped location. So the work is not all I/O Bound. Depending on CPU and network load, one could possibly increase this config to a higher value.|Number of cores| +|`druid.segmentCache.numBootstrapThreads`|How many segments to load concurrently during historical startup.|`druid.segmentCache.numLoadingThreads`| |`druid.coordinator.loadqueuepeon.curator.numCallbackThreads`|Number of threads for executing callback actions associated with loading or dropping of segments. One might want to increase this number when noticing clusters are lagging behind w.r.t. balancing segments across historical nodes.|2| In `druid.segmentCache.locations`, *freeSpacePercent* was added because *maxSize* setting is only a theoretical limit and assumes that much space will always be available for storing segments. In case of any druid bug leading to unaccounted segment files left alone on disk or some other process writing stuff to disk, This check can start failing segment loading early before filling up the disk completely and leaving the host usable otherwise.