Jemalloc 堆内存分析
本文介绍如何为 StarRocks 启用和可视化 Jemalloc 堆内存分析。
备注
- 启用 Jemalloc 堆内存分析可能会影响 StarRocks 的性能。
- 该方案仅适用于 StarRocks v3.1.6 及更高版本。
启用 Jemalloc 堆内存分析
语法：
ADMIN EXECUTE ON <be_id> 'System.print(HeapProf.getInstance().enable_prof())'
启用要求 BE 启动时 jemalloc_conf 中带有 prof:true（默认即为如此），否则语句会失败。当前设置也可以在 information_schema.be_configs 中查看：查询 NAME 为 jemalloc_conf 的那一行，其 VALUE 中的 prof_active 选项即为当前值。
be_id: BE/CN 节点的 ID。可以通过运行 SHOW BACKENDS 或 SHOW COMPUTE NODES 获取 ID。
示例：
mysql> admin execute on 10001 'System.print(HeapProf.getInstance().enable_prof())';
+--------+
| result |
+--------+
| OK |
+--------+
1 row in set (0.00 sec)
可以使用以下语法检查 Jemalloc 堆内存分析是否已启用：
ADMIN EXECUTE ON <be_id> 'System.print(HeapProf.getInstance().has_enable())'
示例：
mysql> admin execute on 10001 'System.print(HeapProf.getInstance().has_enable())';
+--------+
| result |
+--------+
| true |
+--------+
1 row in set (0.01 sec)
可以使用以下语法禁用 Jemalloc 堆内存分析：
ADMIN EXECUTE ON <be_id> 'System.print(HeapProf.getInstance().disable_prof())'
示例：
mysql> admin execute on 10001 'System.print(HeapProf.getInstance().disable_prof())';
+--------+
| result |
+--------+
| OK |
+--------+
1 row in set (0.00 sec)
收集 Jemalloc 堆内存分析
语法：
ADMIN EXECUTE ON <be_id> 'System.print(HeapProf.getInstance().dump_dot_snapshot())'
示例：
mysql> admin execute on 10001 'System.print(HeapProf.getInstance().dump_dot_snapshot())';
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| result |
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| digraph "/home/disk/opt/env/default/be/lib/starrocks_be; 1.0 MB" { |
| node [width=0.375,height=0.25]; |
| Legend [shape=box,fontsize=24,shape=plaintext,label="/home/disk/opt/env/default/be/lib/starrocks_be\lTotal MB: 1.0\lFocusing on: 1.0\lDropped nodes with <= 0.0 abs(MB)\lDropped edges with <= 0.0 MB\l"]; |
| N1 [label="brpc\nInputMessenger\nOnNewMessages\n0.0 (0.0%)\rof 1.0 (100.0%)\r",shape=box,fontsize=8.0]; |
| N2 [label="brpc\nSocket\nProcessEvent\n0.0 (0.0%)\rof 1.0 (100.0%)\r",shape=box,fontsize=8.0]; |
| N3 [label="bthread\nTaskGroup\ntask_runner\n0.0 (0.0%)\rof 1.0 (100.0%)\r",shape=box,fontsize=8.0]; |
| N4 [label="bthread_make_fcontext\n0.0 (0.0%)\rof 1.0 (100.0%)\r",shape=box,fontsize=8.0]; |
| N5 [label="brpc\nInputMessenger\nCutInputMessage\n0.0 (0.0%)\rof 0.5 (50.1%)\r",shape=box,fontsize=8.0]; |
| N6 [label="brpc\npolicy\nParseRpcMessage\n0.5 (50.1%)\r",shape=box,fontsize=43.4]; |
| N7 [label="brpc\nProcessInputMessage\n0.0 (0.0%)\rof 0.5 (49.9%)\r",shape=box,fontsize=8.0]; |
| N8 [label="brpc\npolicy\nProcessRpcRequest\n0.0 (0.0%)\rof 0.5 (49.9%)\r",shape=box,fontsize=8.0]; |
| N9 [label="starrocks\nPInternalServiceImplBase\nexecute_command\n0.0 (0.0%)\rof 0.5 (49.9%)\r",shape=box,fontsize=8.0]; |
| N10 [label="starrocks\nStorageEngineRef\nbind\n0.0 (0.0%)\rof 0.5 (49.9%)\r",shape=box,fontsize=8.0]; |
| N11 [label="starrocks\nexecute_command\n0.0 (0.0%)\rof 0.5 (49.9%)\r",shape=box,fontsize=8.0]; |
| N12 [label="starrocks\nexecute_script\n0.0 (0.0%)\rof 0.5 (49.9%)\r",shape=box,fontsize=8.0]; |
| N13 [label="std\nmake_unique\n0.5 (49.9%)\r",shape=box,fontsize=43.3]; |
| N2 -> N1 [label=1.0, weight=16398, style="setlinewidth(2.000000)"]; |
| N3 -> N2 [label=1.0, weight=16398, style="setlinewidth(2.000000)"]; |
| N4 -> N3 [label=1.0, weight=16398, style="setlinewidth(2.000000)"]; |
| N1 -> N5 [label=0.5, weight=10102, style="setlinewidth(2.000000)"]; |
| N5 -> N6 [label=0.5, weight=10102, style="setlinewidth(2.000000)"]; |
| N9 -> N11 [label=0.5, weight=10086, style="setlinewidth(2.000000)"]; |
| N12 -> N10 [label=0.5, weight=10086, style="setlinewidth(2.000000)"]; |
| N11 -> N12 [label=0.5, weight=10086, style="setlinewidth(2.000000)"]; |
| N1 -> N7 [label=0.5, weight=10086, style="setlinewidth(2.000000)"]; |
| N7 -> N8 [label=0.5, weight=10086, style="setlinewidth(2.000000)"]; |
| N10 -> N13 [label=0.5, weight=10086, style="setlinewidth(2.000000)"]; |
| N8 -> N9 [label=0.5, weight=10086, style="setlinewidth(2.000000)"]; |
| } |
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
29 rows in set (30.22 sec)
可视化 Jemalloc 堆内存分析
将上一步收集的分析文本复制并粘贴到 GraphvizOnline。
然后可以下载可视化的堆内存分析。
示例：
