Difference between jemalloc_active_bytes and node memory

[fuyufjh]

Observed from longevity test OOM.

For example, at 2023-11-21 22:59:00

• jemalloc_allocated_bytes: 8.59 GB
• jemalloc_active_bytes: 9.93 GB
• Node memory (RSS): 12.3 GB

Difference is 2.37 GB.

Previous a very similiar issue #9669 has been solved by #9795

[fuyufjh]

JVM is not used in longevity test.

[fuyufjh]

Since I have no better ideas, now I am trying to manage the LRU watermark according to the system resident memory (rss) instead of Jemalloc's statistics.

Code: main...eric/try_manage_memory_by_rss

Test run: https://buildkite.com/risingwave-test/longevity-test/builds/816

The test was succeeded because the MemoryManager managed to controller the memory at around 7.5GB

JemallocMemoryControl { threshold_stable: 7816840478, threshold_graceful: 8933531975, threshold_aggressive: 10050223472 }

[yuhao-su]

#13648 (comment)

[fuyufjh]

Resolved by #13648