> On Wed, Feb 2, 2011 at 7:00 PM, Craig Ringer > <craig@xxxxxxxxxxxxxxxxxxxxx> wrote: >> Whatever RAID controller you get, make sure you have a battery backup >> unit (BBU) installed so you can safely enable write-back caching. >> Without that, you might as well use software RAID - it'll generally be >> faster (and cheaper) than HW RAID w/o a BBU. > > Recently we had to pull our RAID controllers and go to plain SAS > cards. While random access dropped a bit, sequential throughput > skyrocketed, saturating the 4 lane cable we use. 4x300Gb/s = > 1200Gb/s or right around 1G of data a second off the array. VERY > impressive. This is really surprising. Software raid generally outperform hardware raid without BBU? Why is that? My company uses hardware raid quite a bit without BBU and have never thought to compare with software raid =/ Thanks! --Royce -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
