tag:blogger.com,1999:blog-14455177.post6733213820112746169..comments2024-03-07T18:57:25.977+01:00Comments on Mikael Ronstrom: MySQL Thread Pool: Limiting number of concurrent statement executionsMikael Ronstromhttp://www.blogger.com/profile/07134215866292829917noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-14455177.post-52876574655438663902011-10-21T17:16:16.067+02:002011-10-21T17:16:16.067+02:00The default time limit is 60ms (=6). This is howev...The default time limit is 60ms (=6). This is however configurable and I usually put it at 1 second or so (=100).<br /><br />There is no time limit around locks for the moment, it's based on categorization in the code instead. So we categorize user-level locks such as Row locks, Table Locks and Global Read locks as longer and ignore low level locks such as mutexes.<br /><br />A new query is only started if the number of active queries is zero, it's still possible to get more queries executing in parallel then what is desired if the blocked queries are restarted very close to each other.<br /><br />The thread pool will still in those cases not be worse than without a thread pool.Mikael Ronstromhttps://www.blogger.com/profile/07134215866292829917noreply@blogger.comtag:blogger.com,1999:blog-14455177.post-15817938832811094702011-10-21T16:55:46.228+02:002011-10-21T16:55:46.228+02:00So, what is the time limit for the stall timer? An...So, what is the time limit for the stall timer? And regarding the locks, is the time limit the same? If you have much locking you will of course end up having many queries executing in parallell from each group, which kind of undermines the creation of the groups in the first place.Maxhttps://www.blogger.com/profile/04765710205113959021noreply@blogger.com