…mysql/var innodb_data_file_path = ibdata1:10000M:autoextend innodb_file_per_table innodb_log_group_home_dir = /log/mysql… = 1 innodb_lock_wait_timeout = …MEMORY tables use in the benchmarks ? As otherwise you also need to boost tmp_table_size to deal with implicit memory tables. innodb_file_per_table…
Post: INFORMATION_SCHEMA tables in the InnoDB pluggable storage engine
May 24, 2008 By Leave a Comment
…LOCK_WAITS | | INNODB_LOCKS | | INNODB_TRX | +—————————————-+ The _CMP tables show statistics about compression; they contain a lot of useful information about compression, decompression, memory…
Post: Scaling problems still exist in MySQL 5.5 and Percona Server 5.5
May 20, 2011 By 11 Comments
… looks something like this: SELECT * FROM table WHERE deleted = 0 AND group_id IN…cores. The workload was completely in memory in this test. I have …array_wait_event,rw_lock_s_lock_spin,pfs_rw_lock_s_lock_fu nc,…JOIN::exec,mysql_sel ect,handle_select,execute_sqlcom_select,mysql_execute_command,mysql_…
Post: Working with large data sets in MySQL
July 5, 2007 By 12 Comments
…learn when working with large data things in MySQL is patience and careful planning. Both of …Innodb even if you do not care about Table Locks or transactions). Besides these various trips and …not. Many operations require certain size of table to fit in memory for decent performance. Typically it …
Post: Thinking about running OPTIMIZE on your Innodb Table ? Stop!
December 9, 2010 By 18 Comments
…table which is some 10 times larger than amount of memory I allocated for buffer pool: CREATE TABLE…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…. mysql tables in use 1, locked 0 is number of tables used by transaction in question (meaning it was accessed) and number of tables locked by… memory usage. You can see total memory allocated by Innodb (sometimes it is higher than you anticipated), amount of memory allocated in additional memory…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
… the average query execution time, the number of tmp tables created in memory vs on-disk, percentage of queries that needed full… these pages in memory. What it says though is that, if this query would run on a cold MySQL instance, then it… 0 # rec lock wai 0 0 0 0 0 0 0 0 # Boolean: # Filesort 100% yes, 0% no # Tmp table 100% yes…
Post: DROP TABLE and stalls: Lazy Drop Table in Percona Server and the new fixes in MySQL
June 22, 2012 By 33 Comments
… shared lock on the latch protecting the AHI again Release the shared lock on the latch protecting the AHI Drop Table in Oracle MySQL… a 20M rows table: sysbench –test=oltp –oltp-table-size=20000000 –mysql-table-engine=innodb –mysql-socket=/tmp/mysql_sandbox5524.sock –mysql-db=test –oltp-table-name=sbtest… memory and a software RAID5 array consisting of 4 disks. The version of MySQL used for benchmarking pre 5.5.23 DROP TABLE…
Post: MySQL Query Cache
July 27, 2006 By 70 Comments
…which is quite helpful for MySQL Performance optimization tasks …locking table for write would not invalidate query cache so you can get results even if table is locked…memory – Queries are constantly being invalidated from query cache by table updates, this means number of queries in cache and memory…
Post: Write contentions on the query cache
September 5, 2012 By 5 Comments
…memory), I always got a consistent response time (about 160ms). Of course, I wanted to know more about how MySQL…permissions | 0.000004 | | checking permissions | 0.000004 | | Opening tables | 0.000021 | | System lock | 0.000009 | | init | 0.000022 | | optimizing…
