Although I agree with these recommendations, I don't agree that "Oracle is such an I/O hog". Oracle was designed to perform I/O efficiently and generally does so. Poorly-written SQL can create an I/O bottleneck, but it's not the fault of the RDBMS.
--- [EMAIL PROTECTED] wrote: > You are almost always better off with more spindles to > spread the load over. With fewer disks you get the same > total storage but less flexability in how the I/O is > partitioned between devices. Since Oracle is such an I/O > hog the added flexability can be a real lifesaver. > > Hitachi's claim that there isn't any benefit to spreading > out the I/O may be valid with huge amounts of cache. The > technology for disk I/O manglement is always improving, > so is the quantity of... er... "hooey" available from > sales reps; the answer to your question is probably "both" :-) > > Personally I'd go with more disks using RAID5 w/ a stripe > size equal to the O/S page (e.g., 4x1K or 8x1b for a 4KB > file i/o page or 8x1k for an 8K system page). This avoids > extra overhead from the RAID5 parity writes (you have to > hit all the disks every time anyway) and gives you back > a lot of extra storage over mirroring. Using the RAID5 > w/ a reasonable stripe also allows you to spread the I/O > over multiple RAID's to balance the load -- sine the RAID > set is the "PV" managed by your LVM system. The extra disks > come in handy at this point because you can create more > RAID sets for balancing the load. > > In theory if you have enough cache none of the disk parameters > matter at all. Then it depends largely on your budget for > cache and how well the current Hitachi controllers manage it. > If you don't have infinte faith in their cache management > system then more disks is the better bet. > > > > -- > Steven Lembark 2930 W. Palmer > Workhorse Computing Chicago, IL 60647 > +1 800 762 1582 __________________________________________________ Do You Yahoo!? Check out Yahoo! Shopping and Yahoo! Auctions for all of your unique holiday gifts! Buy at http://shopping.yahoo.com or bid at http://auctions.yahoo.com -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Paul Baumgartel INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
