…memory available, and memory is what really really matters. High-Memory Quadruple Extra Large Instance 68.4 GB of memory… Now let’s come to the MySQL configuration. MySQL Configuration I used Percona Server 5…. the size of the table without secondary indexes is 56G while the size of the table with …
Comment: Benchmarking single-row insert performance on Amazon EC2
May 16, 2012 By 11 Comments
…entire table fits in main memory. Each row is on the order of 30 bytes in the primary table…55GB RAM, Inno would hit a memory wall. Given that Memory sizes are perhaps 10 times bigger than …that Mark wrote http://bazaar.launchpad.net/~mdcallag/mysql-patch/mytools/annotate/head%3A/bench/ibench/iibench…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
…memory they use). Memory Tables MEMORY tables can take memory. There are implicit MEMORY tables which are allocated for query execution, which size can be controlled by tmp_table_size…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
…, MySQL always uses Nested Loop Join to join two or more tables. What this means is that, select rows from first table participating… the workload fits entirely in memory. For the purpose of benchmarking in-memory workload, the InnoDB buffer pool size is set to 6G… to in-memory workload. Also BKA relies on both the join_buffer_size and the read_rnd_buffer_size/mrr_buffer_size and both…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… MySQL 5.6, when the workload fits entirely in memory, because there is no extra cost for memory access at random locations versus memory… MySQL 5.6 w/ read_rnd_bufer_size=4M MariaDB 5.5 MariaDB 5.5 w/ mrr_buffer_size=4M Created_tmp_disk_tables…-memory, in fact MRR adds extra sorting overhead which means that the queries are just a bit slower as compared to MySQL…
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: Dynamic row format for MEMORY tables
September 6, 2011 By 3 Comments
… 2008 Igor Chernyshev of eBay implemented true-VARCHAR support for MEMORY tables for MySQL 5.0. Although this patch did not add the… the data block size at CREATE TABLE time, are in the documentation. What of course interests us is the MEMORY engine performance with… expected memory savings. One quite important feature is missing from this release however: MyISAM tables are still used for temporary tables where the MEMORY tables…
Post: TMP_TABLE_SIZE and MAX_HEAP_TABLE_SIZE
January 19, 2007 By 16 Comments
…_table_size is not enough as MySQL also looks at max_heap_table_size variable and uses lower value as a limit to for in memory temporary table after…@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…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
… constantly referring to the amazing MySQL manual, especially the option and variable reference table. But just as frequently, ….commanual server_idblogpercona.commanual shared_memoryblogpercona.commanual shared_memory_base_nameblogpercona.commanual show_slave_auth_infoblogpercona.commanual …
Post: MySQL Server Memory Usage
May 17, 2006 By 18 Comments
… as full table scans, sorts, or need temporary tables as much as read_buffer_size, sort_buffer_size, read_rnd_buffer_size, tmp_table_size of memory might… single chunk at once others, for example tmp_table_size is rather maximum amount of memory MySQL will allocate for this operation. Note it…
