… like DRBD with virtual machines. First is the disk IO performance hit that comes with DRBD. When you run…-based replication, it looks like you’ll need to wait for the next release of MHA. Q: How do… quite like that in the MySQL world, except maybe MyISAM files on top of a clustered filesystem with an…
Post: Virident vCache vs. FlashCache: Part 2
May 17, 2013 By 3 Comments
… images demonstrate, the no-cache system is being crushed by IO wait. FlashCache and vCache both show improvements, but it’s not…_fast_shutdown = 1 #not innodb options (fixed) back_log = 50 wait_timeout = 120 max_connections = 5000 max_prepared_stmt_count=500000…_size = 4M bulk_insert_buffer_size = 8M myisam_sort_buffer_size = 8M myisam_max_sort_file_size = 10G myisam_repair_threads = 1 myisam_recover
Post: The tool I've been waiting for years
March 18, 2008 By 10 Comments
…been pointed to the nice tool which I was waiting for years to see. It is fincore – little …a clue if slow down happens because of extra IO pressure or just because pages were washed out. …easily add amount of cached data per table for MyISAM and Archive tables to INFORMATION_SCHEMA (or other system…
Post: MySQL MyISAM Active Active Clustering - looking for trouble ?
March 15, 2007 By 4 Comments
… saying you can use MySQL with Active Active Clustering and MyISAM tables if you follow certain rules like enabling external locking… than IO subsystem it may sense configure multiple MySQL servers this way. High availability ? This is where the biggest gotcha is waiting… was not repairing corrupted tables in this configuration even if myisam_repair is set. Space Saving ? As I mentioned replication can…
Comment: Modeling InnoDB Scalability on Multi-Core Servers
January 27, 2011 By 11 Comments
Igor, I’ve had bad luck with myisam under concurrent load on large hardware, even after tuning it (… io wait). For our use cases, we got much better throughput on the big boxes with innodb, even for “read mostly” workloads. Myisam…
Post: Using Multiple Key Caches for MyISAM Scalability
November 26, 2008 By 8 Comments
I have written before – MyISAM Does Not Scale, or it does quite well – two main …scale with one CPU as global lock was held during IO duration, In MySQL 4.1 the lock is held only… a bit of INFORMATION_SCHEMA magic and a bit of waiting on “efficient” Information Schema Query Execution (as you may guess…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
…myisam_recoverblogpercona.commanual myisam_recover_optionsblogpercona.commanual myisam_recover_optionsblogpercona.commanual myisam_repair_threadsblogpercona.commanual myisam_sort_buffer_sizeblogpercona.commanual myisam_stats_methodblogpercona.commanual myisam…
Post: MySQL Users Conference - Innodb
May 9, 2007 By 6 Comments
… DATA INFILE be optimized same way as for MyISAM tables by separate phase of building Indexes ? Will … is however not only reason I can’t wait for this feature to be available. Building index … to test properly before really enabling it. Innodb IO Tuning I should also mention Paul Tuckfield Keynote …
Post: Performance impact of complex queries
January 17, 2007 By 11 Comments
…because of reduced cache efficiency many queries may start waiting on disk at once. In some cases I’… do not require disk head movement, compared to IO requests in random locations other threads are willing … or even careful file transfer if you’re using MyISAM tables. Chop it If you can’t execute …
Post: Choosing innodb_buffer_pool_size
November 3, 2007 By 39 Comments
… but there are other things you need OS cache for – MyISAM tables (mysql database, temporary etc) will need it, .frm file… memory you will have another threads piling up waiting on the same lock till IO completion, while they may well have all… for dedicated Innodb system. If you have fair amount of MyISAM, Archive, PBXT, Falcon or other storage engines then you will…
