…*) (ha_innodb.cc:2284) ==9090== by 0x712F17: ha_initialize_handlerton(st_plugin_int*) (handler.cc:435) ==9090== by 0x7A212A: plugin_initialize(st_plugin…*) (ha_innodb.cc:2284) ==9090== by 0x712F17: ha_initialize_handlerton(st_plugin_int*) (handler.cc:435) ==9090== by 0x7A212A: plugin_initialize(st_plugin… from mutex_exit and there we find a comment: /* A problem: we assume that mutex_reset_lock word is a memory…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
Post: InnoDB compression woes
May 20, 2011 By 14 Comments
… actually was preparing to do complex research, but even first initial results are quite discouraging. My setup: Dell PowerEdge R900, running… utilization is 7%. Obviously we have some mutex serialization problem. Analyzing SHOW INNODB STATUS (SEMAPHORES) for workload with compression tables we can…
Post: InnoDB Flushing: Theory and solutions
April 4, 2011 By 23 Comments
I mentioned problems with InnoDB flushing in a previous post. Before getting to ideas on …. The two most important parameters for InnoDB performance are innodb_buffer_pool_size and innodb_log_file_size. InnoDB works with data in memory…, it is here.) You can see some jumps after the initial warmup stage, but the later throughput is tending toward a…
Post: InnoDB Flushing: a lot of memory and slow disk
March 31, 2011 By 57 Comments
…, 12G innodb_buffer_pool_size, 1G innodb_log_file_size), MySQL 5.5.10 with innodb_adaptive_flushing=ON (default)). The problem here is… disks in software RAID0). As you can see, after the initial warmup, throughput drops constantly, all the way to zero, and… possible solution would be to increase innodb_log_file_size, but that: 1) only delays the problem until later; 2) increases recovery…
Post: Performance problem with Innodb and DROP TABLE
February 3, 2011 By 23 Comments
… threads stall in “Opening Tables” State. Also contrary to my initial suspect benchmarking create/drop table was CPU bound rather than… to this bug at this time. The problem is basically if you’re running innodb_file_per_table=1 the tablespace is… serve performance problems. The stalls can take more than a second for very large buffer pool. If you’re using Innodb tables…
Post: Magic Innodb Recovery self healing
May 22, 2007 By 2 Comments
… monster table these rare corruptions did not cause too much problems to us – as it was not clustered index we always… got lucky. My initial plan was to now dump potentially corrupted tables (in this particular corruption instance Innodb did not print table… do full system restart before attempting recovery. In few instances problems were caused by Kernel bug, inconsistence in OS cache or…
Post: ANALYZE: MyISAM vs Innodb
September 3, 2008 By 9 Comments
… along running ANALYZE TABLE after initial table population and when there are significant changes makes sense. For Innodb as index stats are… accuracy is however a wrong way to look at the problem. Your index stats are a bit off, so what ? What… table is written to actively you should not have this problem; I just did couple of updates to refresh update time…
Post: Hijacking Innodb Foreign Keys
January 2, 2012 By 2 Comments
… – foreign Keys. MySQL supported Foreign Keys for Innodb for many years, yet rudimentary support initially added in MySQL 3.23.44 have…_1` FOREIGN KEY (`parent_id`) REFERENCES `parent` (`parent_id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 INSERT INTO parent(parent_id) VALUES(1… the same value it will not work. This can cause problems to Hibernate and other ORM based applications which often like…
Comment: Hacking to make ALTER TABLE online for certain changes
May 22, 2008 By 26 Comments
…> FLUSH TABLE WITH READ LOCK; mysql> ALTER TABLE City ENGINE=InnoDB; mysql> CREATE TABLE Citytmp LIKE City; mysql> ALTER TABLE Citytmp… box that had 2^31 rows in Innodb with a primary key of signed int which was the initial problem. it worked great!
Post: Bug#12704861
November 20, 2011 By 1 Comment
… serious problem that is fixed in MySQL 5.1.60. I’ll repeat here the full documentation from the release notes: “InnoDB… function that was introduced in the Bug#12612184 fix. The problem that this function was trying to address was that when…” for specifying the mini-transaction where the page should be initialized. Do not allow init_mtr == NULL, because this function is…
