Backport of micro-time patch to mysql 4.1

Backport of micro-time patch to mysql 4.1

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Taking into account 4.1 tree is still popular and is used on many production servers we
decided to make backport of patch to slow-log queries. The patch allows to specify time of slow queries in microseconds and is very helpful in a fight with problematic queries. 4.1 Patch is available here (The original patch was developed by Georg Richter georg at php net)

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Comments (9)

  • Ruslan Zakirov Reply

    Thanks. I’m going to use it once I had time.

    October 1, 2006 at 1:39 pm
  • Michael Monashev Reply

    Thanks.
    Very usfull patch for query profiling.

    Большое спасибо.

    October 5, 2006 at 11:42 am
  • Michael Monashev Reply

    I patch mysql source, but it doesn’t work.

    I can not set long_query_time=0 . The least value of long_query_time – 1. If I set long_query_time=0, “SHOW VARIABLES;” show me long_query_time=1.

    And I see always seconds in slow log: Query_time: 2 Lock_time: 0 .

    How to turn on the patch?

    October 9, 2006 at 6:03 am
  • Vadim Reply

    Michael,

    It looks like you are still using unpatched mysqld.

    The procedure is:
    get sources
    patch with: patch -p1 < patch.slow-micro.4.1.21.diff ./configure --prefix=/usr/local/mysql-micro ...other-options.. make make install In /usr/local/mysql-micro you should get binary

    October 9, 2006 at 7:09 am
  • Michael Monashev Reply

    I do it again, how you write.
    After I run slow query and get this:

    # Time: 061010 0:58:54
    # User@Host: root[root] @ localhost []
    # Query_time: 7 Lock_time: 0 Rows_sent: 1 Rows_examined: 227073
    use mindmix;
    SELECT SQL_CALC_FOUND_ROWS * FROM `topics` WHERE `forum_id` !=1 LIMIT 1;

    Do you have another ideas?

    October 9, 2006 at 2:00 pm
  • Michael Monashev Reply

    I use MyISAM tables…

    October 9, 2006 at 2:01 pm
  • Michael Monashev Reply

    Sorry, I find problem.
    I used old mysqld.

    October 9, 2006 at 2:05 pm
  • peter Reply

    Michael,

    Good you’ve found the problem. Regarding query you have in your example it is slow because of SQL_CALC_FOUND_ROWS – it effectively negates the limit.

    October 9, 2006 at 3:00 pm
  • MySQL Performance Blog » Microslow patch for 5.1.20 Reply

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    July 18, 2007 at 12:27 pm

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