… close pages, saving IO dramatically. No recovery worries – checking/repairing large MyISAM tables in case of MySQL/System crash is painful and… inserts slower as they are random and page splits have to happen. Full table scan for this table would also be slow… – it is often many images from one domain/album are inserted at about same time which makes access locality much better…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
…large_files_supportblogpercona.commanual large_page_sizeblogpercona.commanual large_pagesblogpercona.commanual last_insert…
Post: MySQL Server Variables - SQL layer or Storage Engine specific.
June 8, 2006 By 14 Comments
…inserts 100-1000+ values per single insert statement. concurrent_insert – Enables concurrent insert (while Selects are running) for MyISAM… other storage engines transaction logs, slow query log or general log. flush…MyISAM as key_buffer itself. large_pages – Use of Large Pages for allocation of large…
Post: Predicting how long data load would take
May 24, 2007 By 14 Comments
… type MyISAM may benefit from bulk_insert_tree_size increase myisam_sort_buffer_size or key_buffer_size increase. Innodb typically needs large innodb_buffer_pool_size and large… makes it extremely hard to predict. Especially fact load can slow down dramatically as amount of data loaded in the table…
Post: How many partitions can you have ?
December 5, 2009 By 19 Comments
… with large MySQL data warehouse had the table which was had data merged into it with INSERT ON …compared to only 1.5 times slow down for the same case with just insert. The difference grows even … 1000 partitions – which is over 10x difference. Both MyISAM and Innodb are affected by this issue. The …
Post: MySQL Server Memory Usage
May 17, 2006 By 21 Comments
…execute queries or make operation to swap seriously slowing down. On now legacy 32bit platforms …- bulk inserts may allocate bulk_insert_buffer_size bytes of memory if done to MyISAM tables. myisam_sort…server out of memory MyISAM buffers. MyISAM may allocate buffer which is large enough to contain …
Post: My Innodb Feature wishes
May 4, 2006 By 30 Comments
…compression for its indexes, as MyISAM has which in certain cases …Insert buffer for delete. For Insert operation Innodb uses nice tecnique called Insert Buffer which speeds up inserts…row is going to be slow. For medium sized blobs … both with large number of active threads and with large number of…
Post: To UUID or not to UUID ?
March 13, 2007 By 28 Comments
…access “recent” items more frequently and data set is large auto_increment would work much better than UUID …publish some insert benchmark for this case with larger data size so here they are: I’ve created MyISAM tables…about 200 rows/sec and the it is still slowing down a bit as key file growths. So …
Post: How innodb_open_files affects performance
November 18, 2009 By 4 Comments
…dictionary the operation is slower than MyISAM tables. Though the difference can …writes ? I tried again very simple test inserting the row in each of 100K…300 is not being that large liability even with large number of tables … no any surprises such as surprised slow downs for replacing open files in…
Post: Performance impact of complex queries
January 17, 2007 By 11 Comments
… I could make single full table scan query to slow things that bad, so “ls” would take over 10…, or even careful file transfer if you’re using MyISAM tables. Chop it If you can’t execute this… … LIMIT 1000 and insert sleep 10; in between. By spreading load this way you make sure large portion of the…
