Thanks Baron... Also, curious question.. as you might have used what is called GOOD hw configurarion with RAID 5/10 .. so whats the typical IO (rnd rw) that you archive/expect on high trafficked sites ?
--- On Wed, 3/4/09, Baron Schwartz <ba...@xaprb.com> wrote: From: Baron Schwartz <ba...@xaprb.com> Subject: Re: MySQL Log and Data directories To: dbrb2002-...@yahoo.com Cc: mysql@lists.mysql.com Date: Wednesday, March 4, 2009, 11:40 AM On Wed, Mar 4, 2009 at 1:22 PM, <dbrb2002-...@yahoo.com> wrote: > On a high read/write load.. is it good to split log (binlogs, innodb txn > logs) and data (all tables, innodb tablespace) in different partitions ? > > Anybody had any experience ? > > For example; out of 25 disks array with 142GB 10000rpm... I would like to > keep few disks to logs and rest to data .. is it advised or better to keep > everything in spool so that all spindles can be efficiently managed... > > Thanks in advance There are exceptions to everything I'm about to write, but: Under high read loads, there is no benefit. Under high write loads, there might be. With this many disks, yes. With fewer disks, the relatively trivial sequential log writes will not actually degrade performance much, and the non-trivial performance impact of stealing disks away and dedicating them to the logging workload will make a lot of difference. The real answer is always -- run a benchmark and see. Does the improvement offset things like any kind of penalty the OS imposes on you (e.g. LVM can't take a snapshot across multiple volumes)? -- Baron Schwartz, Director of Consulting, Percona Inc. Our Blog: http://www.mysqlperformanceblog.com/ Our Services: http://www.percona.com/services.html
