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 <200308110313.h7B3DCv06482@candle.pha.pa.us>,
> Bruce Momjian <pgman@candle.pha.pa.us> 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 dalgoda@ix.netcom.com 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
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