apache · morningman · Nov 28, 2020 · Nov 13, 2020
diff --git a/be/src/common/config.h b/be/src/common/config.h
@@ -324,6 +324,9 @@ namespace config {
     // How many rounds of cumulative compaction for each round of base compaction when compaction tasks generation.
     CONF_mInt32(cumulative_compaction_rounds_for_each_base_compaction_round, "9");
 
+    // Merge log will be printed for each "row_step_for_compaction_merge_log" rows merged during compaction
+    CONF_mInt64(row_step_for_compaction_merge_log, "0");
+
     // Threshold to logging compaction trace, in seconds.
     CONF_mInt32(base_compaction_trace_threshold, "10");
     CONF_mInt32(cumulative_compaction_trace_threshold, "2");

diff --git a/be/src/olap/compaction_permit_limiter.cpp b/be/src/olap/compaction_permit_limiter.cpp
@@ -22,6 +22,7 @@ namespace doris {
 CompactionPermitLimiter::CompactionPermitLimiter() : _used_permits(0) {}
 
 bool CompactionPermitLimiter::request(int64_t permits) {
+    DorisMetrics::instance()->compaction_waitting_permits->set_value(permits);
     if (permits > config::total_permits_for_compaction_score) {
         // when tablet's compaction score is larger than "config::total_permits_for_compaction_score",
         // it's necessary to do compaction for this tablet because this tablet will not get "permits"
@@ -40,11 +41,14 @@ bool CompactionPermitLimiter::request(int64_t permits) {
         }
     }
     _used_permits += permits;
+    DorisMetrics::instance()->compaction_waitting_permits->set_value(0);
+    DorisMetrics::instance()->compaction_used_permits->set_value(_used_permits);
     return true;
 }
 
 void CompactionPermitLimiter::release(int64_t permits) {
     _used_permits -= permits;
     _permits_cv.notify_one();
+    DorisMetrics::instance()->compaction_used_permits->set_value(_used_permits);
 }
 } // namespace doris
diff --git a/be/src/olap/compaction_permit_limiter.h b/be/src/olap/compaction_permit_limiter.h
@@ -22,6 +22,7 @@
 
 #include "common/config.h"
 #include "olap/utils.h"
+#include "util/doris_metrics.h"
 
 namespace doris {
 

diff --git a/be/src/olap/merger.cpp b/be/src/olap/merger.cpp
@@ -65,6 +65,10 @@ OLAPStatus Merger::merge_rowsets(TabletSharedPtr tablet,
         RETURN_NOT_OK_LOG(dst_rowset_writer->add_row(row_cursor),
                           "failed to write row when merging rowsets of tablet " + tablet->full_name());
         output_rows++;
+        LOG_IF(INFO, config::row_step_for_compaction_merge_log != 0 && output_rows % config::row_step_for_compaction_merge_log == 0)
+              << "Merge rowsets stay alive. "
+              << "tablet=" << tablet->full_name()
+              << ", merged rows=" << output_rows;
         // the memory allocate by mem pool has been copied,
         // so we should release memory immediately
         mem_pool->clear();

diff --git a/be/src/util/doris_metrics.cpp b/be/src/util/doris_metrics.cpp
@@ -110,6 +110,9 @@ DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(process_fd_num_limit_hard, MetricUnit::NOUNIT
 DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(tablet_cumulative_max_compaction_score, MetricUnit::NOUNIT);
 DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(tablet_base_max_compaction_score, MetricUnit::NOUNIT);
 
+DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(compaction_used_permits, MetricUnit::NOUNIT);
+DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(compaction_waitting_permits, MetricUnit::NOUNIT);
+
 DEFINE_GAUGE_CORE_METRIC_PROTOTYPE_2ARG(push_request_write_bytes_per_second, MetricUnit::BYTES);
 DEFINE_GAUGE_CORE_METRIC_PROTOTYPE_2ARG(query_scan_bytes_per_second, MetricUnit::BYTES);
 DEFINE_GAUGE_CORE_METRIC_PROTOTYPE_2ARG(max_disk_io_util_percent, MetricUnit::PERCENT);
@@ -214,6 +217,9 @@ DorisMetrics::DorisMetrics() : _metric_registry(_s_registry_name) {
     INT_GAUGE_METRIC_REGISTER(_server_metric_entity, tablet_cumulative_max_compaction_score);
     INT_GAUGE_METRIC_REGISTER(_server_metric_entity, tablet_base_max_compaction_score);
 
+    INT_GAUGE_METRIC_REGISTER(_server_metric_entity, compaction_used_permits);
+    INT_GAUGE_METRIC_REGISTER(_server_metric_entity, compaction_waitting_permits);
+
     INT_GAUGE_METRIC_REGISTER(_server_metric_entity, push_request_write_bytes_per_second);
     INT_GAUGE_METRIC_REGISTER(_server_metric_entity, query_scan_bytes_per_second);
     INT_GAUGE_METRIC_REGISTER(_server_metric_entity, max_disk_io_util_percent);

diff --git a/be/src/util/doris_metrics.h b/be/src/util/doris_metrics.h
@@ -133,6 +133,11 @@ class DorisMetrics {
     IntGauge* tablet_cumulative_max_compaction_score;
     IntGauge* tablet_base_max_compaction_score;
 
+    // permits have been used for all compaction tasks
+    IntGauge* compaction_used_permits;
+    // permits required by the compaction task which is waitting for permits
+    IntGauge* compaction_waitting_permits;
+
     // The following metrics will be calculated
     // by metric calculator
     IntGauge* push_request_write_bytes_per_second;

diff --git a/docs/en/administrator-guide/config/be_config.md b/docs/en/administrator-guide/config/be_config.md
@@ -655,6 +655,13 @@ Indicates how many tablets in this data directory failed to load. At the same ti
 
 ### `row_nums_check`
 
+### `row_step_for_compaction_merge_log`
+
+* Type: int64
+* Description: Merge log will be printed for each "row_step_for_compaction_merge_log" rows merged during compaction. If the value is set to 0, merge log will not be printed.
+* Default value: 0
+* Dynamically modify: true
+
 ### `scan_context_gc_interval_min`
 
 ### `scratch_dirs`
@@ -802,6 +809,13 @@ If the parameter is `THREADED`, the model is a non-blocking I/O model,
 
 If the parameter is `THREAD_POOL`, the model is a blocking I/O model.
 
+### `total_permits_for_compaction_score`
+
+* Type: int64
+* Description: The upper limit of "permits" held by all compaction tasks. This config can be set to limit memory consumption for compaction.
+* Default: 10000
+* Dynamically modify: true
+
 ### `trash_file_expire_time_sec`
 
 ### `txn_commit_rpc_timeout_ms`

diff --git a/docs/zh-CN/administrator-guide/config/be_config.md b/docs/zh-CN/administrator-guide/config/be_config.md
@@ -654,6 +654,13 @@ load tablets from header failed, failed tablets size: xxx, path=xxx
 
 ### `row_nums_check`
 
+### `row_step_for_compaction_merge_log`
+
+* 类型：int64
+* 描述：Compaction执行过程中，每次合并row_step_for_compaction_merge_log行数据会打印一条LOG。如果该参数被设置为0，表示merge过程中不需要打印LOG。
+* 默认值： 0
+* 可动态修改：是
+
 ### `scan_context_gc_interval_min`
 
 ### `scratch_dirs`
@@ -799,6 +806,13 @@ Stream Load 一般适用于导入几个GB以内的数据，不适合导入过大
 
 若该参数为`THREAD_POOL`, 该模型为阻塞式I/O模型。
 
+### `total_permits_for_compaction_score`
+
+* 类型：int64
+* 描述：被所有的compaction任务所能持有的 "permits" 上限，用来限制compaction占用的内存。
+* 默认值：10000
+* 可动态修改：是
+
 ### `trash_file_expire_time_sec`
 
 ### `txn_commit_rpc_timeout_ms`