Oh, good point.  By grabbing xlog along with the data files, you do get
a consistent snapshot just like if it had crashed.

---------------------------------------------------------------------------

Mike Castle wrote:
> In article <[EMAIL PROTECTED]>,
> Bruce Momjian  <[EMAIL PROTECTED]> wrote:
> >Also, I assume you have to stop the server just for a moment while you
> >do the freeze, right?
> 
> It depends on if you need known state or just consistent state.
> 
> Taking a snapshot of the system will get you a consistent state just like
> if the machine crashed.  You can restore that snapshot, bring PG back up
> and everything will work.  Of course, you really have no way of knowing
> what transactions were commited and what were not.  
> 
> On the other hand, stop the server/snapshot/start the server gives you not
> only consistency, but a known state.  That is, you know for sure that
> whatever was done before you stopped the server is what was done.
> 
> Which approach is necessary for you depends on your needs, I as always.
> 
> mrc
> -- 
>      Mike Castle      [EMAIL PROTECTED]      www.netcom.com/~dalgoda/
>     We are all of us living in the shadow of Manhattan.  -- Watchmen
> fatal ("You are in a maze of twisty compiler features, all different"); -- gcc
> 
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-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  [EMAIL PROTECTED]               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

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