…the upgrade was completed regardless of its state before updating. This caused some problems for…Alexey Bychko). Percona Server for MySQL was missing help texts in the MySQL client because the … #1107539 (Sergei Glushchenko). Suboptimal code for User Statistics feature has been optimized to make sure…
Post: Is Synchronous Replication right for your app?
May 14, 2013 By 18 Comments
… standard MySQL replication from this instance, since MySQL replication is asynchronous. What about semi-sync MySQL replication? … and you keep track of global achievement statistics in a single table with a row … not safe to retry after the database state changes. retry deadlocks Now we start to get…
Post: Implications of Metadata Locking Changes in MySQL 5.5
February 1, 2013 By 9 Comments
…to MySQL 5.5.3 Metadata Locking behavior prior to MySQL 5.5.3 Prior to MySQL…lock | 0.000009 | | init | 0.000014 | | optimizing | 0.000002 | | statistics | 0.000005 | | preparing | 0.000006 | | executing | 0.000001 |…its time waiting in the “Opening tables” state. Now this behavior with respect to …
Post: How to convert MySQL's SHOW PROFILES into a real profile
February 20, 2012 By 12 Comments
…demonstrate: mysql> SET profiling=1; mysql> pager cat > /dev/null mysql> …snip … | init | 0.000021 | | optimizing | 0.000003 | | statistics | 0.000006 | | cleaning up | 0….id GROUP BY STATE ORDER BY Total_R DESC; +———————-+———-+——-+——-+————–+ | STATE | Total_R | …
Post: MySQL Upgrade Webinar Questions Followup
June 28, 2012 By 7 Comments
… to be depreciated in future MySQL versions also MyISAM tables are essentially at the state they were in MySQL 4.1 while Innodb… either by updating statistics (ANALYZE TABLE) or disabling some of the optimization/statistics related features in new version. Innodb statistics can especially be…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
…. Now, Valgrind does not need much introduction, especially to the MySQL server developers. The Valgrind Memcheck tool, which is synonymous with… of buf_pool->stat are unprotected. These are buffer pool statistics counters: number of read, written, evicted, etc. pages. The more…_schema_table_state) (sql_show.cc:6238) ==9090== by 0x6A5E0C: JOIN::exec() (sql_select.cc:1863) ==9090== by 0x6A7D72: mysql_select(THD…
Post: Percona Server and XtraBackup weekly news, March 5th
March 6, 2011 By Leave a Comment
… very seriously. Yasufumi clarified his idea for XtraDB to store statistics for the ::records_in_range() handler function, instead of accessing… have ever seen a server with dozens of queries in “statistics” state, that’s the bottleneck this feature could help alleviate. We…. We have decided to make innobackupex always back up the MySQL system database, even for partial backups; it contains data that…
Post: Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
…we can use factor of 0.7 and state we can safely run 0.7*16 ~=… take a look at procfs for MySQL process: root@ubuntu:/var/log/mysql# cat /proc/19018/stat 19018… you can get the value from User Statistics *************************** 1. row *************************** USER:user TOTAL_CONNECTIONS: 1 …
Post: Percona XtraDB Cluster reference architecture with HaProxy
June 20, 2012 By 63 Comments
… 13:20:17 [Note] WSREP: State transfer required: Group state: 77c9da88-b965-11e1-0800-ea53b7b12451:97 Local state: 00000000-0000-0000-0000-000000000000… state sequence. Need state transfer. 120619 13:20:19 [Note] WSREP: Running: ‘wsrep_sst_xtrabackup ‘joiner’ ’10.195.206.117′ ” ‘/var/lib/mysql… pair is for haproxy’s statistics page, and the others are for PXC. We will have MySQL listening on 3306 and 3307…
Post: Beware the Innodb Table Monitor
November 29, 2011 By 2 Comments
…contents of the Data dictionary to the mysql error log, which looks something like this: …that were stuck in the ‘Opening Tables’ state, uh-oh. I dug through the … it calls dict_update_statistics and appears to force table statistics to be regenerated for each…
