…query cache query_cache_size = 0 query_cache_type = 0 You can see that the buffer pool is sized…query cache on write heavy workload. OK, so that was all about the configuration of the EC2 instance and MySQL…NOT NULL, `customerid` int(11) NOT NULL, `productid` int(11) NOT NULL, `price` float NOT…-set on…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
…dataset does not fit into memory or if the caches are not warm, this also does not take… Factor of 2 (InnoDB dataset size ~5G). Note that query cache is disabled during these benchmark runs…MySQL 5.5 While with join_buffer_size set to 6M and read_rnd_buffer_size set to 6M, the query time for MySQL…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
…cache reduces memory consumption to be withing the reason. Connection Related Allocations Another set…query execution, which size can be controlled by tmp_table_size and which also only exist for duration of query…can query temporary tables too: mysql>… memory and not): mysql> select * from information…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… case of MySQL 5.5 and ~5 hours in case of MySQL 5.6 and MariaDB 5.5. Note that query cache is disabled… InnoDB buffer pool size is set to 1G and the buffer pool was not warmed up, so that it does not have the relevant… when the correct query execution plan is not used, there is no difference in query times between MySQL 5.5 and MySQL 5.6/MariaDB…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
… in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a… optimizer enhancement Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5 Now let’s take…
Post: Beware large Query_Cache sizes
March 23, 2007 By 3 Comments
… projects with MySQL Query Cache being source of serious problems. One would see queries both for… set query_cache_size relatively high at 256MB or more. It can be seen worse if your query cache size … easiest solution is to decrease query cache size – smaller values do not have such problems but also…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
…MySQL…not_cachedblogpercona.commanual Qcache_queries_in_cacheblogpercona.commanual Qcache_total_blocksblogpercona.commanual Queriesblogpercona.commanual query_alloc_block_sizeblogpercona.commanual query_cache_limitblogpercona.commanual query_cache…
Post: Query Profiling with MySQL: Bypassing caches
September 12, 2007 By 6 Comments
… is simple – because SQL_NO_CACHE only bypasses query cache but it has no change on other caches, which are MySQL Caches – Innodb Buffer Pool and… to clean MySQL table cache (but not Innodb table meta data) or you can do “set global key_buffer_size=0; set global key_buffer_size=DEFAULT…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
…not be in date_id order’; /*!40101 SET character_set…query response times and throughput. Setting up a cluster using the AMI images You can easily test Shard-Query…cache=16384 table-open-cache=128 thread-cache-size=32 thread-stack=256K tmp-table-size=64M transaction-isolation=READ-COMMITTED user=mysql…
Post: New SpecJAppServer results at MySQL and Sun.
November 12, 2008 By Leave a Comment
… MySQL Settings are probably what is the most interesting: MySQL…size = 2M sort_buffer_size = 32k thread_cache = 16 query_cache_size = 0M thread_concurrency = 8 max_heap_table_size=200M log-output = FILE log-slow-queries=/tmp/mysql… be faster. query_cache_size = 0M – query cache disabled. Not a big …
