RE: Also now: raw devices on Sun

Neil Truby wrote > (*) We are setting up two new Sun StoreEdge arrays for a new > Informix installation. These devices come pre-configured as > RAID-5. Obviously we love and fear Art so much that we > wouldn't dare not change it! However, reading through the > performance guide there is a section specifically dealing > with raw devices, in which it states that raw vs file system > is now a non-issue and that large and increasing numbers of > data centres are now just using file system "for very good > reason". It goes on to say that the Sun UFS type has been > optimised in recent years and more-or-less implies that you > shouldn't use raw. Strangely, the text doesn't mention any > particular DBMS but the headline does mention Oracle. > > Any lessons for Informix from this .... Yes - Do not believe everything ignorant lying sales people tell you. The company that sold us our SAN sell Oracle. They told us we could not use raw disk on it. We did, and we benchmarked it against filesystem. Raw gave us always 15-30% better results. (They also sold us a PA support contract recently, but that is another story :-( ) Most kids who set up the expensive RAID systems believe the salesman and do not try any other way, and use filesystem because they have no experience of raw disks and are frightened by it. No doubt you were told there was no point in not using RAID 5 as that is what the system is optimised for, so why believe them about filesystem. Let us know the results after you have benchmarked both ways. :-) Bitter and Twisted Stevenage ________________________________________________________________________ This email has been scanned for all known viruses by the MessageLabs Email Security System. ________________________________________________________________________ sending to informix-list

"Colin Bull" <Colin.Bull@videonetworks.com> wrote in message news:cgkgmc$2a1$1@news.xmission.com... > The company that sold us our SAN sell Oracle. They told us we could not > use raw disk on it. > We did, and we benchmarked it against filesystem. Raw gave us always > 15-30% better results. > (They also sold us a PA support contract recently, but that is another > story :-( ) Oh yes? Tell me about it ...! > Let us know the results after you have benchmarked both ways. :-) Probably won't but will just set it up as raw on the grounds that it'll make it more difficult to understand what's what and thus perpetuate our support contract ;-) > Bitter and Twisted > Stevenage I thought you lived in Cornwall?