From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Boldi <a1426z-u1xxEuL7cY4AvxtiuMwx3w@public.gmane.org>
Subject: Re: [ANNOUNCE] RAIF: Redundant Array of Independent
	Filesystems
Date: Wed, 13 Dec 2006 22:57:24 +0300
Message-ID: <200612132257.24399.a1426z@gawab.com>
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To: Nikolai Joukov <kolya-EX0cT3Az47bauI2f2gSDlQ@public.gmane.org>
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Nikolai Joukov wrote:
> We have designed a new stackable file system that we called RAIF:
> Redundant Array of Independent Filesystems.

Great!

> We have performed some benchmarking on a 3GHz PC with 2GB of RAM and U320
> SCSI disks.  Compared to the Linux RAID driver, RAIF has overheads of
> about 20-25% under the Postmark v1.5 benchmark in case of striping and
> replication.  In case of RAID4 and RAID5-like configurations, RAIF
> performed about two times *better* than software RAID and even better than
> an Adaptec 2120S RAID5 controller.

I am not surprised.  RAID 4/5/6 performance is highly sensitive to the 
underlying hw, and thus needs a fair amount of fine tuning.

> This is because RAIF is located above
> file system caches and can cache parity as normal data when needed.  We
> have more performance details in a technical report, if anyone is
> interested.

Definitely interested.  Can you give a link?


Thanks!

--
Al