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Does anyone can help
Our SQL Server（2019 on linux） instance runs for a period of time, the available memory will become very low.
Some big cost queries that request over than 5 Mb will be queued to request memory.
Checking dmv, it is found that MEMORYCLERK_SQLCONNECTIONPOOL takes up the most memory. What might cause this problem?
And how to release this part of memory？
Thank you very mush
What might cause this problem?
What for a problem?
It is a quite normal behaviour and by design that SQL Server allocate as much memory as it needs and it can get; that's not a memory leakage.
You can limit the memory usage of SQL Server with the "Max. Memory" setting, see Server memory configuration options
Thanks for reply.
I don't think it's a normal situation, we have a higher load instance than this one. MEMORYCLERK_SQLBUFFERPOOL hold the most memory.
Big cost queries has enough available memory to run.
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Hi 12187783,
Welcome to Microsoft Q&A.
In addition, MEMORYCLERK_SQLCONNECTIONPOOL caches information on the server that the client application may need the server to keep track of. You can check with your app developer whether the connections are properly closed after usage.
And please make sure to install the latest CU on SQL Server 2019.
Please refer to this article which might be helpful.
Best Regards,
Amelia
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Thanks for reply, the connections on this instance less then 1500, i don't think this connections could take 149GB memory
@李欣 李欣 , it's not the number of connections but state information per connection (e.g. (server-side cursors) that contributes to connection memory usage. I suspect a leak of prepared query handles that accumulate over time. Make sure client drivers are current and applications properly manage commands and connections properly. Run a server-side trace of rpc_completed events to identify API cursor leaks.
According to this article https://blog.dbi-services.com/sql-server-high-sqlconnectionpool-memory-clerk-consumption/, i have created a trace and did not found this issue
Any other suggestion? thanks.
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SQL Server does not release memory when idle. It is normal, expected and desired for SQL Server to not release memory.