… overhead as compare to MyIsam. I change 90% of my tables to innodb and currently going into queries and db optimization. Could… Innodb. Big table ie. users? comments? etc… i just compared MyIsam to Innodb while loading users from 145000 rows and found… a significant speed gain from MyIsam. Will this be better once i tuned InnoDb settings? and add query cache? Thanks a lot for…
Post: Return of the Query Cache, win a Percona Live ticket
August 26, 2011 By 4 Comments
… query cache, the only possible improvement is to disable the cache completely, and people don’t care beyond that. Here’s my favorite query cache… to “Waiting on query cache mutex” when the query cache mutex is taken. This makes it really obvious when the query cache is a bottleneck. Oracle… you used to be able to see that you had MyISAM problems really easily when you had a screen full of…
Post: Beware large Query_Cache sizes
March 23, 2007 By 3 Comments
… of consulting projects with MySQL Query Cache being source of serious problems. One would see queries both for MyISAM and Innodb tables mysteriously stalling for few seconds with “NULL” in State column. These could be troubleshooted to waiting on Query Cache…
Post: MyISAM Scalability and Innodb, Falcon Benchmarks
October 12, 2007 By 10 Comments
… benchmark shows following results for MyISAM using MySQL 5.0.45 run on 4 Core System: Threads queries/sec 1 161 2… key_cache is a problem is benchmark run with disabled key_cache (=0). Results for MyISAM with key_buffer_size=0 Threads queries/sec… can see Falcon perform extremely poorly when single query executed being 1/3rd of MyISAM and 1/6th of Innodb. On other…
Post: Cache Performance Comparison
August 9, 2006 By 73 Comments
… are: Cache Type Cache Gets/sec Array Cache 365000 APC Cache 98000 File Cache 27000 Memcached Cache (TCP/IP) 12200 MySQL Query Cache (TCP/IP) 9900 MySQL Query Cache (Unix… (`k`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8; INSERT INTO `test` VALUES (‘test’,'MyTestString’); 3) You need all caches to work, ie query cache enabled, memcached…
Post: MySQL MyISAM Active Active Clustering - looking for trouble ?
March 15, 2007 By 4 Comments
… with Active Active Clustering and MyISAM tables if you follow certain rules like enabling external locking, disabling query cache and delayed key writes… was not repairing corrupted tables in this configuration even if myisam_repair is set. Space Saving ? As I mentioned replication can… really being compatible with such setup. As Oli describes even query cache which was implemented many years ago in 4.0 was…
Post: table_cache negative scalability
November 16, 2009 By 23 Comments
… not always works – we’ve seen performance issues with large query_cache_size also sort_buffer_size and read_buffer_size may… the disk during this read-only benchmark. Why ? Because for MyISAM tables table header has to be modified each time the… – in this version table_cache was significantly redone and split in table_open_cache and table_definition_cache and I assumed the behavior…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
…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…
Post: InnoDB vs MyISAM vs Falcon benchmarks - part 1
January 8, 2007 By 117 Comments
… pread system call MyISAM uses to access data and retrieving from OS cache is not scaled. READ_KEY_POINT_LIMIT Query: SELECT name… the performance of LIMIT queries will be fixed before release. MyISAM shows stable result. InnoDB is better than MyISAM by 58% in case…_FTS Query: SELECT min(dob) FROM $tableName The hardest query performs a scan of all million rows. InnoDB is better than MyISAM by…
Post: Using MyISAM in production
June 17, 2006 By 35 Comments
… unnoticed with MyISAM storage engine. This hidden corruption may later cause crashes wrong query results and further data corruption. Partial updates. MyISAM is… out. Lack of row cache. MyISAM tables only have indexes cached in key_buffer while data is cached in OS cache. It is performance issue…
