John, I had already updated the online manual at http://www.innodb.com. It warns now about the 2 GB limit on memory usage in Linux x86.
InnoDB does not use the record_buffer of MySQL at all. But sort_buffer is used. I think the danger lies in server overload: many ORDER BY queries may get stuck in the 'sorting data' phase which will raise memory usage to 2 GB. Best regards, Heikki Tuuri Innobase Oy --- InnoDB - transactions, row level locking, and foreign key support for MySQL See http://www.innodb.com, download MySQL-Max from http://www.mysql.com John Kemp wrote in message ... >Heikki & Jeremy, > >Thanks again for your help. I'll try it out and see how things go. I >will just note that in most of the MySQL documentation talks about how >one can set key_buffer or innodb_buffer_pool up to 75% of your maximum >memory, which in the case of our db machines is 4GB. I have been >monitoring our memory usage under load, and even with the numbers I >listed below, I have not yet seen a server crash from 200 simultaneous >connections, which has been our peak so far. We did see this a while >back on an earlier version (we're now running 3.23.45-max) but our >server has been running like this for 45 days and counting. > >So I guess this is more of a case (as Jeremy seemed to be suggesting) >that this *might* happen if we have a lot of simultaneous, tricky >queries (when we'd see lots of sort_buffer and record_buffer get >allocated for each connection/thread) > >This also implies that if you're mostly using Innodb tables for querying >that you probably wouldn't see this happening, because: > >1) Innodb doesn't lock the whole table - so simultaneous queries on the >same table will get done faster, and thus memory will be freed up quicker. >2) Does querying or updating the Innodb tablespace effect record_buffer >and sort_buffer anyway? > >The more I think about it, the more I realize that since we started >doing work with Innodb tables, our database memory problems have >basically gone away. > >Any thoughts on that? > >John >Director, Software Development >Streetmail Inc. --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
