Re: the SAS and RAID-5 question

At our location we see the benefit of keeping the SAS temp files on a non-RAID volume, just for the fact that it won't sacrifice write performance due to RAID 5 (although, if you are using hardware based RAID 5 with a cached controller, the write performance is pretty good). However, you may be sacrificing availability. If you are in the middle of a SAS job and the "Temp" drive decides to fail and you have no redundancy, your job will fail. We guess that it all comes down to which is more important performance or availability. If you need 100% availability with no exceptions, we would go with the 4 RAID arrays. If you need the absolute best performance, and can tolerate possible down time, go with the 3 RAID and 1 non-RAID 5 (for best results, set up the non-RAID 5 array as RAID 0 (striped across multiple disks).

Hope this helps! (from me and our LAN group) Mark Terjeson Washington State Department of Social and Health Services Division of Research and Data Analysis (RDA) (360) 902-0741 (360) 902-0705 fax mailto:terjemw@dshs.wa.gov