Chris wrote: >And your statement about it being faster >on RAID 0 or 1 is incorrect. RAID 5 is >faster, as the write job is split up across >the drives and each drive writes it's own >piece of data at the same time as the others.
No, Chris, it is you who are incorrect. RAID 5 arrays are the worst performing for writes than any other common raid type. This is because two write one block, you need to read data from all the disks in the array, calculate parity, and then write out both the data block and parity block. Even RAID 1 sets are faster for writes than RAID 5. Also, Anthony's original post did specifically mention RAID 0 for the transaction logs and tempdb, not RAID 10. RAID 0 is certainly not a good idea on any production server, since one drive failure will bring the application down. Tempdb and logs need redundancy, too, if only for uptime. :::Ryan Malayter :::Network Engineer :::Bank Administration Institute :::Chicago, Illinois, USA :::PGP Key: http://www.malayter.com/pgp-public.txt -----Original Message----- From: Szlucha, Chris [mailto:[EMAIL PROTECTED]] Sent: Monday, February 04, 2002 2:06 PM To: NT 2000 Discussions Subject: RE: SQL Server and RAID Levels Forgive me if I'm wrong, but Ed wasn't saying to use both RAID 0 and RAID 1, but rather what is sometimes called RAID 10, or more properly RAID 0+1. It is a mirrored RAID setup. Speed and redundancy, but it's the most costly of the bunch. And your statement about it being faster on RAID 0 or 1 is incorrect. RAID 5 is faster, as the write job is split up across the drives and each drive writes it's own piece of data at the same time as the others. -Chris -----Original Message----- From: Paul Timmerman [mailto:[EMAIL PROTECTED]] Sent: Monday, February 04, 2002 3:00 PM To: NT 2000 Discussions Subject: RE: SQL Server and RAID Levels It would all depend on the importance and size of the data. If there is going to be a large amount of data I would stick with thye RAID 5 for overall redundancy. In this case, I would recommend using 15K rpm drives if that is monetarily feasable. Yes, writing is a lot faster on RAID 0 or 1, but does this meet your redundancy needs? I would be very wary of placing the logs on a RAID 0 drive. That is NO redundancy. Again, depending on the importance of the data data, it might be okay. However, remeber that RAID 0 means that if that drive goes, so goes the transaction log and your ability to do a point in time recovery. >From: Ed Esgro <[EMAIL PROTECTED]> >Reply-To: "NT 2000 Discussions" <[EMAIL PROTECTED]> >To: "NT 2000 Discussions" <[EMAIL PROTECTED]> >Subject: RE: SQL Server and RAID Levels >Date: Mon, 4 Feb 2002 14:46:54 -0500 > >How about using 0+1 on the SQL Database. You get speed and redundancy >at >the >price of space. Much faster then RAID5. > > >-----Original Message----- >From: Anthony L. Sollars [mailto:[EMAIL PROTECTED]] >Sent: Monday, February 04, 2002 2:40 PM >To: NT 2000 Discussions >Subject: SQL Server and RAID Levels > > >I am building another production SQL Server for our services team, and >have configured in my default configuration: 2 x 18gig SCSI on RAID 1 = >OS & Pagefile 2 x 73gig SCSI on RAID 0 = Logs & tempDB >4 x 73gig SCSI on RAID 5 = SQL Database > > >The problem is the SQL engineers are questioning the performance of >RAID5 for their needs. > >We are using RAID 0 on the logs because this is transactional data that >is not important, and we don't need redundancy here just sheer speed. >But they are saying that RAID 0 should be used isntead of RAID5 on the >4 drive array. The bulk of the work on this RAID5 will be data >manipulation, where they willl run sql scripts that compress and >organize the tables in the database. >In my opinion RAID 5 is good for this also. > >-TOny >Thanks for any advice > >------ >You are subscribed as [EMAIL PROTECTED] >Archives: http://www.swynk.com/sitesearch/search.asp >To unsubscribe send a blank email to [EMAIL PROTECTED] > >------ >You are subscribed as [EMAIL PROTECTED] >Archives: http://www.swynk.com/sitesearch/search.asp >To unsubscribe send a blank email to [EMAIL PROTECTED] _________________________________________________________________ Join the world's largest e-mail service with MSN Hotmail. http://www.hotmail.com ------ You are subscribed as [EMAIL PROTECTED] Archives: http://www.swynk.com/sitesearch/search.asp To unsubscribe send a blank email to [EMAIL PROTECTED] ------ You are subscribed as [EMAIL PROTECTED] Archives: http://www.swynk.com/sitesearch/search.asp To unsubscribe send a blank email to [EMAIL PROTECTED] ------ You are subscribed as [email protected] Archives: http://www.swynk.com/sitesearch/search.asp To unsubscribe send a blank email to [EMAIL PROTECTED]
