Backport of micro-time patch to mysql 4.1
Posted by Vadim
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)
Posted by Vadim @ 2:05 am :: patch, production
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9 Comments
Thanks. I’m going to use it once I had time.
Comment :: October 1, 2006 @ 1:39 pm
Thanks.
Very usfull patch for query profiling.
Большое спасибо.
Comment :: October 5, 2006 @ 11:42 am
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?
Comment :: October 9, 2006 @ 6:03 am
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
Comment :: October 9, 2006 @ 7:09 am
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?
Comment :: October 9, 2006 @ 2:00 pm
I use MyISAM tables…
Comment :: October 9, 2006 @ 2:01 pm
Sorry, I find problem.
I used old mysqld.
Comment :: October 9, 2006 @ 2:05 pm
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.
Comment :: October 9, 2006 @ 3:00 pm
[...] patch has been there for some time, but only for earlier MySQL editions such as 4.1 and 5.0. Now it’s also available for the latest [...]
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