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From: Daniel Phillips <phillips@phunq.net>
To: david@lang.hm
Subject: Re: [ANNOUNCE] Ramback: faster than a speeding bullet
Date: Mon, 31 Mar 2008 21:07:48 -0700
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Cc: David Newall <davidn@davidnewall.com>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Willy Tarreau <w@1wt.eu>, linux-kernel@vger.kernel.org
References: <200803092346.17556.phillips@phunq.net> <200803310440.33019.phillips@phunq.net> <alpine.DEB.1.00.0803311727500.31200@asgard.lang.hm>
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On Monday 31 March 2008 17:28, david@lang.hm wrote:
> On Mon, 31 Mar 2008, Daniel Phillips wrote:
> 
> > On Tuesday 18 March 2008 09:36, david@lang.hm wrote:
> >> P.S. 8xPCI-e slots are only able to do 2GB/s of data transfer, in an
> >> earlier post Daniel claimed that you needed 3GB/s of disk to mirror to the
> >> disk, so the scenerio listed above looses 1/3 of it's performance compared
> >> to what was being claimed earlier.
> >
> > Each Violin 1010 has two 8xPCI-e interfaces.
> 
> but if you use them for redundancy by hooking them to two machines you can 
> only use one of them on your active system.

That is why you use two Violin 1010 boxes, each connected to two
servers.  The resulting mirror will have roughly 1 GByte/sec write
bandwidth and 3 GByte/sec read bandwidth.  Fast enough for you?  No?

Well then...

Continue this idea to achieve whatever bandwidth you want to the ramdisk,
subject to finding server motherboards that can take lots of PCI-e 8x
cards, which are admittedly rare, but see "have your checkbook ready".

Regards,

Daniel