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anaxagoras

ZFS and Raid-Z

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I'm just looking for some info on ZFS and raidz, anyone know how it compares to raid 5 or how raid2z compares to raid 6?

I'd probably be looking at hardware raid 6, raidz is software only, any massive sata controllers out there that don't do raid?

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I'm just looking for some info on ZFS and raidz, anyone know how it compares to raid 5 or how raid2z compares to raid 6?

I'd probably be looking at hardware raid 6, raidz is software only, any massive sata controllers out there that don't do raid?

I think that the best thing to do would be to either try it for yourself or if you can, run a search on here to find out some of the results that I had published a while back on raidz speeds and compare it to published values for conventional RAID5/6.

I think that's the best way of going about it. Hope that helps. Thanks.

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I'm just looking for some info on ZFS and raidz, anyone know how it compares to raid 5 or how raid2z compares to raid 6?

I'd probably be looking at hardware raid 6, raidz is software only, any massive sata controllers out there that don't do raid?

RAIDZ = RAID 5 on ZFS with the write hole fixed. Nobody has made a simple RAID5 for ZFS.

RAIDZ2 = the same, but like RAID 6

Because raidz is done with ZFS, you also have the checksumming and other overhead going on. So raw performance of ZFS can be slightly worse than other file systems, and raidz can be slightly worse than raid5. But overall, with raidz, you get all kinds of good stuff that is there BECAUSE the good outweighs the bad.

http://www.opensolaris.org/jive/index.jspa?categoryID=1

ps: be warned that opensolaris doesnt have the greatest hardware support, and many common nics and sata adapters aren't really supported

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I'm just looking for some info on ZFS and raidz, anyone know how it compares to raid 5 or how raid2z compares to raid 6?

I'd probably be looking at hardware raid 6, raidz is software only, any massive sata controllers out there that don't do raid?

RAIDZ = RAID 5 on ZFS with the write hole fixed. Nobody has made a simple RAID5 for ZFS.

RAIDZ2 = the same, but like RAID 6

Because raidz is done with ZFS, you also have the checksumming and other overhead going on. So raw performance of ZFS can be slightly worse than other file systems, and raidz can be slightly worse than raid5. But overall, with raidz, you get all kinds of good stuff that is there BECAUSE the good outweighs the bad.

http://www.opensolaris.org/jive/index.jspa?categoryID=1

ps: be warned that opensolaris doesnt have the greatest hardware support, and many common nics and sata adapters aren't really supported

Another note that is often missed is that because raidz and raidz2 are both controlled by Solaris (effectively), CPU speeds and in particular memory bandwidth speeds become EXTREMELY important. Luckily, anybody who's building a system typically have more control of what CPU and memory they choose to use than the storage processor and the associated cache.

And unfortunately, loomy is right - Solaris is rather picky about hardware support. But when it does work though, it works pretty much non-stop.

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