On Friday 30 Nov 2001 16:33, Jason Burfield wrote: First of all, the idea of data loss because one disk has gone bad on RAID-5 is not possible. RAID-5 specifically allows you to loose up to 1 disk at any one time, and stay active.
The reason why RAID-5 is not recommended for MySQL is speed. RAID-5 requires parity bits to be calculated and spread across all your disks for every write you do. For every read, this all has to be decoded. This means that the file system is slower, which is not very helpful for a database. I am running SCSI RAID-5 (Linux - software only), and I have had no problems. I have lost a disk from a stripe before, and no data was ever corrupted. You just put in a new disk and rebuild the data on it. It's as simple as that. RAID tends not to mess up the performance too much is you are running SMP (if you've got multiple CPUs, it is easier to find time on them to do the RAID-5 checksumming) and you have lots of RAM to keep things nicely cached. Regard. Gordan > I currently run a system with Raid 5. I have had one disk drop, however, > no data was lost. That is one of the beauties of RAID 5, you have a > spare disk that takes over. > > I too had heard originally that running MySQL on a RAID 5 was a bad idea > (this, after I already had it running...), however, I have not had any > problems at all. > On Thu, 2001-11-29 at 17:34, Lionlike MySQL Email List wrote: > > Just one quick question... I've heard that running a database in a > > system using RAID isn't a good idea on RAID 5, but works fine with > > mirroring (0, 0/1, 0/5). Does anyone out there have experience with > > MySQL on RAID 5, or know how MySQL performs in a RAID 5 environment? My > > concern is loss of data due to a drive going bad. At least that what > > I've heard could happen. Thanks, --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
