From: Daniel Phillips <phillips@phunq.net>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: [ANNOUNCE] Ramback: faster than a speeding bullet
Date: Sat, 15 Mar 2008 13:25:48 -0800
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On Saturday 15 March 2008 13:56, Alan Cox wrote:
> > RAID controllers do not have half a terabyte of RAM. Also, you are always
> > invited to choose between speed (write back) and reliability (write through).
> 
> The write back ones are also battery backed properly, and will switched
> to write through (flushing out the cache) on the first sniff of a low
> battery signal.

In other words, exactly how ramback works.

> The decent ones (the kind used in serious business) also let you swap the
> battery backed RAM module to another card in the event of a failure of a
> card so you can complete recovery.

Right, just like the Violin 1010, whose PCI-e cable can be hotplugged
into a different server.  Or plugged into two servers at the same time,
because each 1010 has two PCI-e interfaces, so this can be done without
manual intervention.

See, we really are talking about the same thing.  Except that ramback
does it bigger and faster.

Daniel
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