On Wed, Jul 21, 2010 at 1:38 PM, JavaWebDev <javaweb...@verizon.net> wrote: > 1. WD Caviar Black > ************************ > Can they be used with in raidz or mirrors?
We use the 500 GB versions attached to 3Ware controllers (configured as Single Disk arrays). They work quite nicely. > With the new models the firmware is locked and you can't change the TLER > settings. When a drive detects an error it's going to hang a long time > trying to correct the problem before it reports the error to ZFS right? What > type of errors are we talking about, bad blocks or something more serious? Haven't noticed any issues. The RAID controller notes the odd (maybe 1 per fortnight) timeout, but then reconnects the drive without ZFS noticing. We have yet (2 years) to have a drive timeout and cause ZFS to offline the drive. > 2. WD Caviar Greens > ************************* > I was hoping to use low power drives like the WD Caviar Greens. In addition > to the TLER issue they have an issue with too many load/unload cycles that > would wear out the drive faster when used in raid configs including zfs. WD > put out a utility that could increase the time to reduce the load/unload > cycles (wdidle.exe). Does this still work with the caviar green drives? Even > if it does work, changing the idle behavior is going to make it use more > energy right? > > Are Caviar Green drives (the new ones anyway) completely unsuitable for a > ZFS based back-up or NAS server? We use 8x 1.5 TB WD Green drives, since they were really inexpensive at the time, and looked good on paper. We've been regretting it ever since. I actively pray for these to die so that I can replace them with Seagate 1.5 TB drives. For a home setup where you don't care about disk throughput, these may be workable. Otherwise, avoid the entire Green/GP series of WD disks. They are, to put it nicely, crap. Don't ask for an elaboration unless you want a multiple page diatribe on the horrors of using these drives. Just don't use them outside of the home. We also use WD Caviar Blue 500 GB, and RE2/RE3 500 GB drives attached to 3Ware controllers without issues. Finally, we also use Seagate Barracuda 7200.11 500 GB and 1.5 TB drives with great success. As wel as Seagate ES.2 500 GB drives. Basically, anything other than the WD Green/GP drives works well. > 5. Mirror vs raidz > ********************** > Can any of the issues with consumer drives be reduced using one type of vdev > over the other? Will adding a seperate log or cache device help? An L2ARC will help with reads, especially if using raidz vdevs. > For a backup server, which would you choose, 4 drives in raidz, 4 drives in > raidz2, 3 drives in raidz with hs, 4 drives with 2 mirrored pairs? Only 4 drives? Do they still make servers that only use 4 drives? ;) It all depends on which you prefer, raw throughput or redundancy. For best performance, use 2x 2-drive mirrors. For best redundancy, use 1x 4-drive raidz2. For middle-of-the-road performance/redundancy, use 1x 4-drive raidz1. Note: newegg.ca has a sale on right now. WD Caviar Black 1 TB drives are only $85 CDN. -- Freddie Cash fjwc...@gmail.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
