Re: BBU still needed with SSD?

From: Bruce Momjian
Subject: Re: BBU still needed with SSD?
Date: ,
Msg-id: 201107190159.p6J1xuT07770@momjian.us
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In response to: Re: BBU still needed with SSD?  (Andy)
Responses: Re: BBU still needed with SSD?  (Andy)
List: pgsql-performance

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BBU still needed with SSD?  (Andy, )
 Re: BBU still needed with SSD?  (Craig Ringer, )
  Re: BBU still needed with SSD?  (David Rees, )
   Re: BBU still needed with SSD?  (Andy, )
    Re: BBU still needed with SSD?  (Bruce Momjian, )
     Re: BBU still needed with SSD?  (Andy, )
      Re: BBU still needed with SSD?  (Greg Smith, )
 Re: BBU still needed with SSD?  (Yeb Havinga, )
  Re: BBU still needed with SSD?  (Florian Weimer, )
   Re: BBU still needed with SSD?  (Yeb Havinga, )
    Re: BBU still needed with SSD?  (Florian Weimer, )
     Re: BBU still needed with SSD?  (Yeb Havinga, )
      Re: BBU still needed with SSD?  (Florian Weimer, )
       Re: BBU still needed with SSD?  (Yeb Havinga, )
        Re: BBU still needed with SSD?  (Greg Smith, )
         Re: BBU still needed with SSD?  (Klaus Ita, )
 Re: BBU still needed with SSD?  (Greg Smith, )

Andy wrote:
>
>
> --- On Mon, 7/18/11, David Rees <> wrote:
>
> > >> In this case is BBU still needed? If I put 2 SSD
> > in software RAID 1, would
> > >> that be any slower than 2 SSD in HW RAID 1 with
> > BBU? What are the pros and
> > >> cons?
> >
> > What will perform better will vary greatly depending on the
> > exact
> > SSDs, rotating disks, RAID BBU controller and
> > application.? But
> > certainly a couple of Intel 320s in RAID1 seem to be an
> > inexpensive
> > way of getting very good performance while maintaining
> > reliability.
>
> I'm not comparing SSD in SW RAID with rotating disks in HW RAID with
> BBU though. I'm just comparing SSDs with or without BBU. I'm going to
> get a couple of Intel 320s, just want to know if BBU makes sense for
> them.

Yes, it certainly does, even if you have a RAID BBU.

--
  Bruce Momjian  <>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +


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