… a regression that could cause a memory leak if query cache was used together with InnoDB. Bug fixed #1170103. Fixed the… #1171941. Fixed the CVE-2012-5627 vulnerability, where an unprivileged MySQL account owner could perform brute-force password guessing attack on… the MySQL 5.6 version, which removed MyISAM internal temporary table mutex contention. Bug fixed #1179978. Release notes for Percona Server for MySQL…
Post: MySQL and the SSB - Part 2 - MyISAM vs InnoDB low concurrency
May 22, 2013 By Leave a Comment
… sort via ALTER TABLE ENABLE KEYS. my.cnf [mysqld] datadir=/mnt/mysql56/data basedir=/usr/local/mysql socket=/var/lib/mysql/mysql.sock user=justin innodb_buffer_pool_size=64G innodb_log_file_size=4G innodb_file_per_table… innodb_undo_logs=32 innodb_old_blocks_time=0 table_open_cache=2048 table_definition_cache=16384 innodb_flush_method=O_DIRECT key_buffer…
Post: ZFS on Linux and MySQL
May 24, 2013 By 17 Comments
… to start the snapshot while holding a “flush tables with read lock” and the flush operation will…maybe it is related to better raid controller write cache use. Even the fairly slow gzip-1 mode…ZFS on Linux is a very interesting solution for MySQL backup servers. All backup solutions have an impact …
Post: Rotating MySQL slow logs safely
April 18, 2013 By 7 Comments
…, I described a solution for keeping the caches of a MySQL standby server hot using MySQL slow logs with long_query_time set… MySQL bug 65481 explains that the HUP signal also flushes tables in addition to logs. Flushing tables can impact running queries. Disable MySQL slow… practices: /var/mysql/slow_query.log { nocompress create 660 mysql mysql size 1G dateext missingok notifempty sharedscripts postrotate /usr/local/bin/mysql -e ‘select…
Post: MySQL 5.6 - InnoDB Memcached Plugin as a caching layer
March 29, 2013 By 10 Comments
… the entire cache is cleared (think restarting a memcache node). This is where a persistent cache can be invaluable. Enter MySQL 5.6 with the memcached plugin… As part of the standard MySQL 5.6… per/cmd 0.0951 ms range per/cmd InnoDB MySQL Select (same table): Fetching [1,000,000] items: 441573 ms total 0…
Post: MySQL and Percona Server in LinkBench benchmark
May 8, 2013 By 18 Comments
…. Percona Server 5.5 outperforms MySQL in about 2x times. Both MySQL 5.5.30 and MySQL 5.6.11 demonstrate notable drops… we can see small performance drop in MySQL 5.6. In IO-bound cases MySQL still has performance issues around mutexes and… sync_binlog=0 max_connections=5000 table_open_cache=5000 table-definition-cache=1000 query_cache_size=0 query_cache_type=0 performance_schema=0 #56only…
Post: More on MySQL transaction descriptors optimization
April 26, 2013 By Leave a Comment
…= 8 innodb_io_capacity = 2000 max_connections=5000 table_open_cache=5000 query_cache_type=OFF performance_schema=0 warmup To warmup …120 –max-requests=0 –percentile=99 –mysql-user=root –mysql-db=sbtest8t1M –mysql-table-engine=INNODB –mysql-socket=/tmp/mysql.sock –oltp-point-selects=1 –oltp…
Comment: MySQL Partitioning - can save you or kill you
April 30, 2013 By 45 Comments
… partitioned table, as, depending on the size of the partitions, the whole partition can be cached, as opposed to a single table, where probably only recently read records will be cached, resulting in more… other column, these could easily be quicker on a partitioned table, as Mysql can fire off one thread per partition (at least…
Comment: MySQL 5.6 - InnoDB Memcached Plugin as a caching layer
March 30, 2013 By 10 Comments
… http://dev.mysql.com/doc/refman/5.6/en/innodb-memcached-internals.html there are some caching settings to play with: “Table cache_policies… to use the traditional memcached engine as the backstore (cache-only), or both (caching). In the last case, if memcached cannot find a key in memory, it searches for the value in an InnoDB table…
Post: Is Synchronous Replication right for your app?
May 14, 2013 By 18 Comments
… memory (Battery or capacitor-backed write cache), etc., but the principle is basically the… MySQL replication from this instance, since MySQL replication is asynchronous. What about semi-sync MySQL … maintained in separate tables and there also exists a users_groups table to define the relationship…
