Skip site navigation (1) Skip section navigation (2)

Re: Battery Backed Cache for RAID

From: "Merlin Moncure" <merlin(dot)moncure(at)rcsonline(dot)com>
To: "Alvaro Herrera" <alvherre(at)alvh(dot)no-ip(dot)org>
Cc: "Pgsql-Performance" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Battery Backed Cache for RAID
Date: 2005-09-14 20:17:06
Message-ID: 6EE64EF3AB31D5448D0007DD34EEB3417DD346@Herge.rcsinc.local (view raw or flat)
Thread:
Lists: pgsql-performance
> On Wed, Sep 14, 2005 at 11:28:43AM -0700, Jeffrey W. Baker wrote:
> > On Wed, 2005-09-14 at 11:25 -0700, Peter Darley wrote:
> > > 	I'm getting a new server for our database, and I have a quick
> question
> > > about RAID controllers with a battery backed cache.  I understand
that
> the
> > > cache will allow the cache to be written out if the power fails to
the
> box,
> > > which allows it to report a write as committed safely when it's
not
> actually
> > > committed.
> >
> > Actually the cache will just hold its contents while the power is
out.
> > When the power is restored, the RAID controller will complete the
writes
> > to disk.  If the battery does not last through the outage, the data
is
> > lost.
> 
> Just curious: how long are the batteries supposed to last?
 
For the length of time it will take for you to get fired for not getting
the server running plus one hour :).

Merlin

pgsql-performance by date

Next:From: John A MeinelDate: 2005-09-14 20:40:25
Subject: Re: Battery Backed Cache for RAID
Previous:From: Alvaro HerreraDate: 2005-09-14 20:03:24
Subject: Re: Battery Backed Cache for RAID

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group