MySQL Forums
Forum List  »  Performance

Re: MySQL 5.6 update doubled IOs
Posted by: Dimitri Kravtchuk
Date: April 05, 2013 06:24AM

Hi Christian,

no, no need more test - Olav pointed out that MRR is used in your case because of the "read_rnd_buffer_size = 2M" setting (as the buffer is big, MRR has a lower cost), while I'm using a default value..

in any case, we all agree that for "LIMIT 1" case it looks like a bug, so should be fixed. (if you want you may log it yourself to be updated on changes (and just add a link to this forum thread)).

while for the initial issue with higher IO activity on 5.6 nothing is clear for me :-) so, if you can collect some stats with my own tools, then I'll probably say you more :-)

here is the howto:
- http://dimitrik.free.fr/blog/archives/2012/09/mysql-performance-collecting-stats-from-your-workload.html

Rgds,
-Dimitri

Options: ReplyQuote


Subject
Views
Written By
Posted
1276
March 20, 2013 08:52AM
1179
March 27, 2013 11:44PM
1218
March 28, 2013 07:49PM
1136
April 02, 2013 12:20AM
1186
April 02, 2013 09:57PM
Re: MySQL 5.6 update doubled IOs
1236
April 05, 2013 06:24AM
1158
April 10, 2013 08:31AM


Sorry, you can't reply to this topic. It has been closed.

Content reproduced on this site is the property of the respective copyright holders. It is not reviewed in advance by Oracle and does not necessarily represent the opinion of Oracle or any other party.