Excerpts from Filipus Klutiero's message of Thu Oct 27 16:49:30 -0400 2011: > Package: mysql-server-5.1 > Version: 5.1.58-1 > Severity: wishlist > > Hi, > I'm opening a ticket about a general problem, but this is food for > thought too. Please apologize and triage as you wish. > > I am a web developer working on a web application which has a large > schema. There are currently over 200 tables in the schema, all of them > MyISAM. > Every few weeks, I'll install a new version of the application and > create a new MySQL database for it. > > My development desktop was installed in April 2010, and has been getting > slower and slower to boot, to the point where I'm thinking about > reinstalling since months. There is a lot of disk read during boot, and > I never knew precisely why. Today I realized by accident that mysqld was > taking about 10% CPU for a very long time during boot, and went to > investigate why. > > Restarting mysql seems to happen fast (less than 5 seconds), but it was > in fact causing significant CPU usage for a long time. I found that this > CPU usage happened every time mysql was started, and then that this came > from /etc/mysql/debian-start. I then discovered it came from > check_for_crashed_tables(). The function contains: >
My first question would be why are you using MyISAM for anything important. Or rather, why are you using MyISAM, at all. I know that we are still stuck with MySQL 5.1 and, therefore, have MyISAM as the default, but its become quite obvious that it is such a limited data storage engine, that it should not be used by any serious application. I would recommend that you alter all of your tables to InnoDB, and start explicitly setting the engine to InnoDB during your create tables. You will get a far more resilient system with nearly the same speed on most common sane operations. There is no need to check these tables, because like a journaled filesystem, one can trust that the database is in a consistent state or not just by looking at the headers and journals. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
