…. Index Condition Pushdown Traditional B-Tree index lookups have some limitations in cases such as range scans, where index parts after…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
…) with a Scale Factor of 2 (InnoDB dataset size ~5G). Note that query cache is disabled during these benchmark runs and that the…, o_orderdate, o_shippriority order by revenue desc, o_orderdate LIMIT 10; In-memory workload Now let’s see how effective…_size increased to 6M, the query time was ~300s while when both the join_buffer_size and the read_rnd_buffer_size/mrr_buffer_size…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
…query execution, which size can be controlled by tmp_table_size and which also only exist for duration of query…size variable which allows you to limit size of MEMORY tables (the limit …2039977928 + 2382090360) Page hash 127499384 Dictionary cache 512619219 (509995888 + 2623331) File system 294352 (…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… variable to control the MRR buffer size mrr_buffer_size. Both buffer sizes default to 256K in MySQL 5….MySQL 5.6 and MariaDB 5.5. Note that query cache is disabled during these benchmark runs and that …_name, c_address, c_comment order by revenue desc LIMIT 20; In-memory workload Now let’s see …
Post: MySQL caching methods and tips
April 4, 2011 By 4 Comments
… cache methods The MySQL query cache When the query cache is enabled, MySQL examines each query to see if the contents have been stored in the query cache… you need Both Memcached and the MySQL query cache are limited in size. If you try to cache more information than you can store, space…
Post: MySQL Server Memory Usage
May 17, 2006 By 18 Comments
…where – these are key_buffer_size, innodb_buffer_pool_size, innodb_additional_memory_pool_size, innodb_log_buffer_size, query_cache_size. If you’re using …OS, File Cache and other applications. For 32bit envinronment you also should keep 32bit limits into account and probably limit “mysqld” size to …
Post: Impact of the sort buffer size in MySQL
October 25, 2010 By 8 Comments
…), I decide to verify and benchmark performance while varying the size of the sort_buffer. It is my understanding that the… required to perform 12 queries like ‘select * from sorttest order by data limit 78000,1′ with, of course, the query cache disabled. I also verified that during the whole process, the computer never swapped and I pre-warmed the file cache before…
Post: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
…cache size, but size range This is minor one. Unlike you would typically see Falcon uses minimum and maximum sizes for row cache… index covered queries is great optimization for wide range of queries. [+] Ordered … transaction. [-] Isolation Modes So far limited amount of isolation modes is supported…
Post: Another scalability fix in XtraDB
January 23, 2009 By 13 Comments
…for experiments, and I played with queries SELECT name FROM sbtest WHERE country_id = ? LIMIT 5 against table CREATE TABLE IF …\ –table_cache=2048 \ –query_cache_size=0 \ –innodb_data_file_path=ibdata1:100M:autoextend \ –innodb_buffer_pool_size=6GM \ –innodb_additional_mem_pool_size=20M \ –…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
… Queriesblogpercona.commanual 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_prealloc…
