…: InnoDB fragmentation may hurt your query significantly, especially when data is not in buffer_pool and execution goes to read from disk Fragmentation… records by secondary key To check if you query affected by fragmentation you can use Innodb_scan_pages_contiguous ; Innodb_scan_pages_jumpy statistics…
Post: MySQL File System Fragmentation Benchmarks
March 21, 2008 By 28 Comments
… Innodb tables on ext3 filesystem. Here is what I found: The fragmentation we speak in this article is filesystem fragmentation or internal table fragmentation…… So it does not work very well. Note: As I checked later contrary to my expectation this filesystem was created without… suffers worse than Innodb – Innodb extent allocation works (perhaps would be good option for MyISAM as well) – Innodb suffers fragmentation less if it stores…
Post: Innodb Double Write
August 4, 2006 By 23 Comments
… just between their execution. Reasons for splitting could be file fragmentation – most file systems use 4K block sizes by default so… check as it is not the only reason for partial page writes. I just know they tend to happen and before Innodb… location and fsync() called the second time. Now on recovery Innodb checks doublewrite buffer contents and pages in their original location. If…
Comment: Percona build7 with latest patches
December 2, 2008 By 26 Comments
… innodb_io_patches.patch mirror_binlog.patch mysqld_safe_syslog.patch innodb_locks_held.patch innodb_show_bp.patch innodb_check_fragmentation.patch innodb_io_pattern.patch innodb_fsync_source.patch innodb_show_hashed_memory…
Comment: Statistics of InnoDB tables and indexes available in xtrabackup
September 14, 2009 By 6 Comments
…” : http://dev.mysql.com/doc/refman/5.0/en/innodb-monitors.html#innodb-table-monitor ) So, honestly, I don’t grasp what… “contiguousness”. (contiguousness like http://www.percona.com/docs/wiki/patches:innodb_check_fragmentation ?)
Comment: InnoDB: look after fragmentation
November 5, 2009 By 12 Comments
….6-log Percona Server (GPL), 12.6, Revision 200 the “innodb_scan%” status variables do not exist, but in Server version… these is documented http://www.percona.com/docs/wiki/patches:innodb_check_fragmentation but there’s no indication they are deprecated…..or what…
Comment: Percona Server 5.5.8 Beta Release
February 20, 2011 By 16 Comments
why remove SHOW PATCHES command? and how about adding innodb_check_fragmentation patch to it, i think it is very useful,thanks
Post: Learning about MySQL Table Fragmentation
May 1, 2008 By 19 Comments
… single page (16K reads). In case of non fragmented table you would see Innodb sequential read-ahead kick in which does reads… not logically fragmented and Innodb is reading data in large blocks – this can happen in case Innodb table file is itself fragmented. To check if…. P.S It would be cool to get Innodb objects (data and Index) fragmentation statistics which actually should not be that hard…
Post: Improved InnoDB fast index creation
November 6, 2011 By 4 Comments
…Status | Duration | +——————————+———–+ | starting | 0.000054 | | checking permissions | 0.000004 | | checking permissions | 0.000004 | | init | 0….is fragmentation. Fast index creation results in much less fragmented…ALTER TABLE … ENGINE=InnoDB for InnoDB tables and thus, …
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
… we can run to show any table / index fragmentation, without having to run the OPTIMIZE? HT: Since … up in “show innodb statusâ€. select * from table where id=5 show innodb status: Hash table size … the status or bug in implementation. I’ll check with Alexander or check myself to see what it could …
