… MySQL Consulting work or even more frequently. IO Bound workload is quite different from CPU bound one, which happens when your working set (normally… application back to speed. The cases when going from CPU bound to IO bound hits the most is there a lot of rows… 100 rows analyzed by the query and these rows are “random access” to large tables (so chances they would require physical…
Post: How multiple disks can benefit for single client workload ?
April 26, 2008 By 4 Comments
…terms. For me IO is IO bound workload – disks are moving and CPU sits idle. With such terminology there…easy to see if system is IO bound or CPU bound, while to understand if MySQL goes through more… Though this does not help dramatically for many “random” update queries. After pages are fetched and …
Post: Impact of logging on MySQL’s performance
February 10, 2009 By 7 Comments
…=2000 Depending on workload different InnoDB buffer was used. In CPU-bound case innodb_buffer_pool_size=2G In IO-bound case innodb_buffer… with 1, 20 and 100 database connections Results To reduce random error the test was run 3 times per each parameter… about performance impact in case of CPU-bound workload. The performance impact is negligibly small in IO-bound workload even if all queries are logged…
Post: InnoDB thread concurrency
June 5, 2006 By 4 Comments
… of methods like read by index or sequential read or random read); write_row; update_row; delete_row; At start of… threads for each CPU and Disk resource. For Disk IO bound workload you could only account number of disks and for CPU bound only number… bound operation even if rest of workload is CPU bound so same value for variables would not work well in all cases. For many workloads…
Comment: MySQL on Amazon RDS part 1: insert performance
March 15, 2011 By 37 Comments
… not be random IO bound workload. It should be mainly CPU bound. If you want IO bound workload you have to have some keys which are random, for example if you ad SHA1(id) as a key it would become io bound on insert at…
Comment: MySQL on Amazon RDS part 1: insert performance
March 15, 2011 By 37 Comments
… not be random IO bound workload. It should be mainly CPU bound. If you want IO bound workload you have to have some keys which are random, for example if you ad SHA1(id) as a key it would become io bound on insert at…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 17 Comments
… are possible especially on high IO pressure workloads. Q7: Does Innodb has any protection from … When Innodb decides to schedule sequential read-ahead, random read ahead ? HT: InnoDB schedules a sequential …official InnoDB, though. PZ: If your load is CPU bound and you’re scaling out you can …
Comment: Linux schedulers in tpcc like benchmark
January 31, 2009 By 19 Comments
… sequentially written log files to the more write-costly spreaded/random innodb data file. Whatever, I stand corrected now, thank you…, which sometimes does matters. I suspect a mixed workload (alternated write intensives, reads, and cpu bound moments, not just huge sustained writes) would…
Post: Join performance of MyISAM and Innodb
May 29, 2006 By 6 Comments
… of Join speed for MyISAM and Innodb storage engines for CPU bound workload, this is when data size is small enough to fit… compression for character keys which makes it perform slower for random lookups MyISAM generally has lower processing overhead due to its… to request next row matching index Note: This applies to CPU bound workload with all content fitting in memory. In other cases situation…
Post: Just do the math!
July 6, 2009 By 4 Comments
…/sec scanned if data is in memory. In this case CPU is normally the limiting factor. In case we hit the… “random” access patterns – some form of index accesses, joins etc may be slowed down 100-1000 then going from CPU bound to IO bound workload…
