…_io_threads = 4 innodb_file_per_table = 1 ## Disabling query cache query_cache_size = 0 query_cache_type = 0 You can see that the buffer pool is… performance. Other then that, I have also disabled query cache to avoid contention caused by query cache on write heavy workload. OK, so that… to reduce chances of log flush storms and disabling the query cache.
Comment: Too many connections? No problem!
March 15, 2012 By 28 Comments
…-slow-queries=/var/log/mysql-slow-queries.log long_query_time=15 log-queries-not-using-indexes query_cache_type=1 query_cache_size=32M thread_cache_size=30 table_cache…
Comment: MySQL Query Cache
March 21, 2012 By 69 Comments
We have query_cache_type= DEMAND but still a single query that contains multiple joins with four tables uses “checking query cache” state even though the SQL SELECT statement does not contain SQL_CACHE…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… of MySQL 5.6 and MariaDB 5.5. Note that query cache is disabled during these benchmark runs and that the disks… be incremented by TWO. It does not actually mean that queries with MRR are performing badly. The interesting thing is that… what are the good and bad query execution plans. a. Bad Plan id select_type table type possible_keys key key_len ref…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
… Scale Factor of 2 (InnoDB dataset size ~5G). Note that query cache is disabled during these benchmark runs and that the disks… not make much of a difference in the query times. Conclusion BKA improves the query time by a huge margin for IO…. I intend to run tests to see what specific types of queries would benefit from Hash Join as compared to Nested Loop…
Post: MariaDB 5.3 is released as GA!
March 5, 2012 By 17 Comments
… schemas Microsecond time resolution for DATETIME and similar time-based types, as well as microseconds in SHOW PROCESSLIST Group commit for… Faster queries through speedier joins, faster subqueries, and elimination of useless tables in joins Thread pooling and a segmented key cache for…
Post: MySQL Query Cache
July 27, 2006 By 69 Comments
… in “Cache everything” mode. In certain caches you might want to cache only some of the queries – in this case you can set query_cache_type to “DEMAND” and use only SQL_CACHE hint for queries which you want to have cached – such as SELECT SQL_CACHE col…
Post: Return of the Query Cache, win a Percona Live ticket
August 26, 2011 By 4 Comments
…. As of MySQL 5.5, the query cache mutex isn’t hit at all if query_cache_type is zero. We made some related changes… query cache, the only possible improvement is to disable the cache completely, and people don’t care beyond that. Here’s my favorite query cache… to “Waiting on query cache mutex” when the query cache mutex is taken. This makes it really obvious when the query cache is a bottleneck. Oracle…
Post: Should we give a MySQL Query Cache a second chance ?
April 10, 2011 By 63 Comments
… work well with queries containing dynamic comments as well as simply multiple instances by the same query typed in by different …Query Cache is most useful for complex expensive queries, for which tracking exact rows used from query syntax may be hard. Query Cache Storage Engines MySQL Query Cache…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
…query_alloc_block_sizeblogpercona.commanual query_cache_limitblogpercona.commanual query_cache_min_res_unitblogpercona.commanual query_cache_sizeblogpercona.commanual query_cache_typeblogpercona.commanual query_cache_wlock_invalidateblogpercona.commanual query…
