"Scott Marlowe" <scott.marlowe@xxxxxxxxx> writes: > 2008/11/5 Christian Schröder <cs@xxxxxxxxx>: >> Tomasz Ostrowski wrote: >>> >>> This is wrong. RAID5 is slower than RAID1. >>> You should go for RAID1+0 for fast and reliable storage. Or RAID0 for >>> even faster but unreliable. >>> >> >> I did not find a clear statement about this. I agree that RAID10 would be >> better than RAID5, but in some situations RAID5 at least seems to be faster >> than RAID1. > > For certain read heavy loads RAID-5 will beat RAID-1 handily. After > all, from a read only perspective, a healthy RAID-5 with n disks is > equal to a healthy RAID-0 with n-1 disks. Uhm, and for a read-heavy load a RAID-1 or RAID 1+0 array with n disks is equal to a healthy RAID-0 with n disks. RAID-5 should never beat any combination of RAID-0 and RAID-1 with the same number of drives at read performance. It's advantage is that you get more capacity. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com Ask me about EnterpriseDB's PostGIS support! -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
