…SET GLOBAL test_a.key_buffer_size=39514112; | | SET GLOBAL test_b.key_buffer_size=28390400; | +———————————————+ 2 rows in set…
Post: How much memory can MySQL use in the worst case?
February 12, 2009 By 17 Comments
… some “global buffers” that aren’t really global. Suppose you set sort_buffer_size to 128K — I can quite well connect and say “set @@sort_buffer_size…_packet). And keys for user locks! I set my max_allowed_packet bigger and ran the following on my laptop: mysql> set @a := repeat…
Post: MySQL Server Memory Usage
May 17, 2006 By 21 Comments
… global buffers which are allocated at start and always where – these are key_buffer_size, innodb_buffer_pool… you know memory requirements with current settings and increase/decrease values appropriately. Some may… to run MySQL server out of memory MyISAM buffers. MyISAM may allocate buffer which is …
Post: What to tune in MySQL Server after installation
September 29, 2006 By 118 Comments
…during Interview for people to work as MySQL DBAs or be involved with MySQL Performance in some way is …if all of key_buffer is used over time – it is not rare to see key_buffer being set to 4G while … Note: as you can see all of these are global variables. These variables depend on hardware and mix …
Post: MySQL Server Variables - SQL layer or Storage Engine specific.
June 8, 2006 By 14 Comments
…MySQL versions did not bother naming variables with storage engines prefix. This is why we have key_buffer, not “myisam_key_buffer…key_buffer itself. large_pages – Use of Large Pages for allocation of large global areas such as Innodb Buffer Pool, Key Buffer…
Post: Wanted: Better memory profiling for MySQL
May 18, 2008 By 4 Comments
… often higher than innodb_buffer_pool_size) substract memory used by other global buffers such as query_cache_size and key_buffer and will in… using some of the buffers temporary based on per connection settings ? It also could be memory leak in MySQL or runaway stored procedure…
Post: Choosing innodb_buffer_pool_size
November 3, 2007 By 39 Comments
…Buffer Pool. This of course assumes your database is large so you need large buffer pool, if not – setting buffer…MySQL needs – these include MySQL buffers – query cache, key_buffer, mysql threads, temporary tables, per thread sort buffer… example sum up all your global buffers plus add 1MB for each…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…read. If the InnoDB buffer pool is set to 22GB, it’…, I’ll paste in mysql> show global variables like ‘%table_size%’; +———————+———–+ | Variable_name | …mysql.* tables, running mk-duplicate-key-checker to find redundant indexes, and so on. As with settings and status, these set…
Post: Read Buffers, mmap, malloc and MySQL Performance
September 12, 2007 By 8 Comments
…buffer_size variable affects connection speed. This is not something you would expect right ? me too. Not only global…with strace) are great tools for MySQL Performance analyses. Too many…the buffer is allocated the more pages needs to be set…be used for Innodb Buffer Pool and Key Buffer but could be …
Comment: Database problems in MySQL/PHP Applications
November 6, 2006 By 13 Comments
… mainly # MySQL. # # You can copy this file to # /etc/my.cnf to set global options, # mysql-data-dir/my.cnf to set server-… [isamchk] key_buffer = 256M sort_buffer_size = 256M read_buffer = 2M write_buffer = 2M [myisamchk] key_buffer = 256M sort_buffer_size = 256M read_buffer = 2M write_buffer = 2M …
