mysql/5.0.45 …

August 12, 2009 2:09 pm UTC | In Tech

I recently did some performance testing with a few big tables on mysql/5.0.45 under CentOS and noticed a sharp drop in query speed a few minutes after restarting mysql. More tests showed mysql/5.0.51a or newer don’t have this problem. OK, I guess a picture is worth a thousand words… (SELECT queries only, and also mysql buffer size is huge, so disk I/O is minimal during test.)
mysql_performance
It’s most likely due to mysql bug 21074 (fixed in mysql/5.0.50). Unfortunately mysql/5.0.45 is the version that ships with CentOS 5.3 and some other Redhat-derived Linux distro. Consider upgrading if you are using mysql/5.0.45 and your mysql server appears to be heavily CPU-bound.

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  1. 我还在学呢。

    Comment by 亦歌 — August 13, 2009 2:33 am UTC #

  2. 这种测试都是用什么测试工具搞的呢?测试结果用什么画的呢?

    Comment by 有颜色的猫 — August 14, 2009 4:30 am UTC #

  3. 测试就几行 Python …… 画图是 matplotlib

    Comment by atppp — August 14, 2009 10:14 am UTC #

  4. 我囧,我被这玩意坑惨了……

    Comment by fancy — August 14, 2009 10:59 pm UTC #

  5. 你好!请问一下,是否能够将kbs的数据转换到discuz或者其他的论坛程序?

    Comment by aiyi — August 19, 2009 10:52 pm UTC #

  6. “测试就几行 Python …… 画图是 matplotlib”

    发个测试的脚本,我也测测手头的服务器看看,3x:)

    Comment by mysql_study — August 20, 2009 8:32 pm UTC #

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