Re: Backup strategies

Ivan Voras a écrit :
> Jesper Krogh wrote:
>>[...]
>> It worked when I tested it, but I may just have been darn lucky.
>
> No, it should be ok - I just didn't catch up with the times :) At least
> that's my interpretation of this paragraph in documentation:
>
> """Some backup tools that you might wish to use emit warnings or errors
> if the files they are trying to copy change while the copy proceeds.
> This situation is normal, and not an error, when taking a base backup of
> an active database; so you need to ensure that you can distinguish
> complaints of this sort from real errors..."""
>
> It looks like PostgreSQL freezes the state of the "data" directory in
> this case (and new data goes only to the transaction log - pg_xlog),
> which effectively creates an application-level snapshot. Good to know.
>

Nope. Even files in data directory change. That's why the documentation
warns against tools that emit errors for files that change during the copy.


--
Guillaume.
 http://www.postgresqlfr.org
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