… disks are 4 5.4K disks in Software RAID5. Also note that the following changes were made in the MySQL config: optimizer…_bufer_size=4M MariaDB 5.5 MariaDB 5.5 w/ mrr_buffer_size=4M Created_tmp_disk_tables 1 1 1 1 1 Created_tmp_tables 1 1 1 1 1 Handler_mrr_init N/A 0 0…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
… the disks are 4 5.4K disks in Software RAID5. Also note that the following changes were made on MySQL 5.6… time is for MySQL 5.6 which takes 0.16s less as compared to MySQL 5.5 While with join_buffer_size set to…_size=6M & mrr_buffer_size=6M MariaDB 5.5 Hash Join Disabled w/ join_buffer_size=4M & mrr_buffer_size=4M Created_tmp_disk_tables 0 0 0 0 0 0 Created_tmp_tables…
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: TMP_TABLE_SIZE and MAX_HEAP_TABLE_SIZE
January 19, 2007 By 16 Comments
…@ted.mysql.internal +6 -0 BUG #4291 fix: new configuration option “disk-tmp-table-size” introduced to set maximum expected on-disk temporary table size and avoid…@ted.mysql.internal +7 -0 BUG #4291: max_heap_table_size affects creation of disk-based temporary table fix: the new system variable memory_tmp_table_size is… restrictions. So now we’re getting 4 variables instead of two ? It is unclear about tmp_table_size – if it is going to be…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
…0 0 0 0 0 0 0 0 # Tmp tables 0 0 0 0 0 0 0 0 # Tmp disk tbl 0 0 0 0 0 0 0 0 # Tmp tbl size 0 0 0 0 0 0 0 0 # Query size 0 21.63k 71 71 71 71 0 71 # InnoDB: # IO r bytes 0 0 0 0 0 0 0 0 # IO r ops 0 0 0 0 0 0 0 0…tables involved and the query execution plan used by MySQL…
Post: Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
…0 552967 4096 26345 18446744073709551615 0 0 17 0 0 0 0 0 0 The #14 and #15 here is kernel and user CPU usage of MySQL…0 0 0 0 0 0 0 0 # Tmp tables 0 0 0 0 0 0 0 0 # Tmp disk tbl 0 0 0 0 0 0 0 0 # Tmp tbl size 0 0 0 0 0 0 0 0 # Query size…
Post: How much overhead is caused by on disk temporary tables
August 16, 2007 By 26 Comments
… wa st 0 4 116 60064 9084 547160 0 0 5 44 96 103 2 0 94 3 0 0 3 116 56248 9104 549212 0 0 2 2023…, 0 rows affected (0.03 sec) mysql> set global max_heap_table_size=1000000000; Query OK, 0 rows affected (0.00 sec) mysql> set global tmp_table_size=1000000000; Query OK, 0… have mysql> set max_heap_table_size=1000000000; Query OK, 0 rows affected (0.00 sec) mysql> set tmp_table_size=1000000000; Query OK, 0 rows affected (0.00 sec) mysql> select…
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 11 Comments
… different MySQL configurations, I didn’t try out different MySQL …size = 16M max_heap_table_size = 64M thread_cache_size = 32 query_cache_size = 0 tmp_table_size = 64M key_buffer_size = 8M bulk_insert_buffer_size = 8M myisam_sort_buffer_size…0 447.1 34.0 7.4 0% 2.4 5.4 23.4 49.6 0.6 0% 0.0 0.6 85% 0…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
…-thread-sleep-delay=0 innodb-use-sys-stats-table innodb-write-io-threads=4 join-buffer-size=16M key-buffer-size=64M local-…TABLES symbolic-links table-definition-cache=16384 table-open-cache=128 thread-cache-size=32 thread-stack=256K tmp-table-size=64M transaction-isolation=READ-COMMITTED user=mysql…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…0 | 0…tmp_tables and Created_disk_tmp_tables, I’ll paste in mysql> show global variables like ‘%table_size%’; +———————+———–+ | Variable_name | Value | +———————+———–+ | max_heap_table_size | 268435456 | | tmp_table_size…
