Cherry pick #73081 to 24.3: Fix possible overestimate memory tracking#73121
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robot-clickhouse merged 3 commits intobackport/24.3/73081from Dec 11, 2024
Merged
Cherry pick #73081 to 24.3: Fix possible overestimate memory tracking#73121robot-clickhouse merged 3 commits intobackport/24.3/73081from
robot-clickhouse merged 3 commits intobackport/24.3/73081from
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Before this patch the untracked_memory was dumped before reseting the current_thread which could lead to leaking some of untracked_memory in `ThreadStatus::detachFromGroup` [1]. In particular I found that the local_data (which is 136 bytes) can be "leaked" that way. [1]: https://github.com/ClickHouse/ClickHouse/blob/8999fdd95ea98fa083133d5cdf64ee149cd7f864/src/Interpreters/ThreadStatusExt.cpp#L292-L306 This pops up on one of clusters where I noticed that the difference between MemoryTracking and MemoryResident keeps growing over the time. the difference grows ~200KiB per second - 16.5GiB per day. That cluster has tons MVs triggered from Buffer/Distributed (i.e. now query context), and this is indeed is the reason for leaking local_data, since in this case there is no thread group in the query, and it is created explicitly in `InterpreterInsertQuery::buildChain` [1]. [1]: https://github.com/ClickHouse/ClickHouse/blob/20ccb638ba00103f116855afbc473950ef2b867b/src/Interpreters/InterpreterInsertQuery.cpp#L321 Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
Fix possible overestimate memory tracking
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Original pull-request #73081
This pull-request is a first step of an automated backporting.
It contains changes similar to calling
git cherry-picklocally.If you intend to continue backporting the changes, then resolve all conflicts if any.
Otherwise, if you do not want to backport them, then just close this pull-request.
The check results does not matter at this step - you can safely ignore them.
Note
This pull-request will be merged automatically. Please, do not merge it manually (but if you accidentally did, nothing bad will happen).
Troubleshooting
If the PR was manually reopened after being closed
If this PR is stuck (i.e. not automatically merged after one day), check #73081 for
pr-backports-createdlabel and delete it.Manually merging will do nothing. The
pr-backports-createdlabel prevents the original PR #73081 from being processed.If the conflicts were resolved in a wrong way
If this cherry-pick PR is completely screwed by a wrong conflicts resolution, and you want to recreate it:
pr-cherrypicklabel from the PRYou also need to check the original PR #73081 for
pr-backports-created, and delete if it's presented there