Thanks a lot Faustin
I found an useful description of MDEV-29988 in a comment to one of its duplicates, and it matches quite well our application scenario for the database connection that cause the memory leak according to information_schema.PROCESSLIST.memory_used (prepared statements executed maaany times, string comparisons) we reproduced the issue on a test machine, and we will try to downgrade to 10.5.15 MAtteo https://jira.mariadb.org/browse/MDEV-30096?focusedCommentId=243814&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-243814 [serg]Sergei Golubchik<https://jira.mariadb.org/secure/ViewProfile.jspa?name=serg> added a comment - 2022-11-28 22:20 Yes, <https://jira.mariadb.org/browse/MDEV-29988> was in 10.6.11 too. But let's first check the preconditions: * you use prepared statements * you prepare once and then execute many thousands of times before deallocating the statement * your statements contains a string comparison with strings in different (but compatible) character sets (e.g. utf8 and latin1). if all that matches your use case you could be affected by <https://jira.mariadb.org/browse/MDEV-29988> . If you do, then * every execution of such a prepared statements will allocate more memory * all memory will be freed when a statements is deallocated (explicitly or when the client disconnects) * time to deallocate a prepared statement is proportional to the number of times it was executed and workarounds could be * deallocate prepared statements more often * rewrite statements to avoid comparing strings in different character sets or wait for the next release that will have it fixed On Tue, 10 Jan 2023 13:36:02 +0100 Faustin Lammler <faus...@fala.red> wrote: > Hi, > first of all, thank you all for the excellent (and detailed) report! > > I don't see anything that could be related with Debian packaging of > MariaDB and so I suggest you check directly upstream. > > I have searched into https://jira.mariadb.org and the closest report > that I can come with is https://jira.mariadb.org/browse/MDEV-29988. I do > not forward this bug report to it because I am not sure that this is the > same problem. > > There is also https://jira.mariadb.org/browse/MDEV-29097 that may give > some ideas on how to find a workaround until the next release happen. > > Cheers! > > -- > Faustin > GPG: F652 BCD1 1AA8 8975 F010 48A5 390A 2F27 832A 5C79 If you received this email in error, please notify the sender and read our confidentiality and data protection disclaimer: https://www.pdxeng.ch/our-company/e-mail-disclaimer/