Re: Detecting corrupted pages earlier

Tom Lane wrote:
> Kevin Brown <kevin@sysexperts.com> writes:
> > Tom Lane wrote:
> >> Basically, one should only turn this variable on after giving up on the
> >> possibility of getting any data out of the broken page itself.  It would
> >> be folly to run with it turned on as a normal setting.
> 
> > This statement should *definitely* go into the documentation for the
> > option, then...
> 
> Andrew Sullivan expressed concern about this, too.  The thing could
> be made a little more failsafe if we made it impossible to set
> ZERO_DAMAGED_PAGES to true in postgresql.conf, or by any means other
> than an actual SET command --- whose impact would then be limited to
> the current session.  This is kind of an ugly wart on the GUC mechanism,
> but I think not difficult to do with an assign_hook (it just has to
> refuse non-interactive settings).
> 
> Comments?

Perhaps better would be to throw a message message any time it is turned
on, reminding them it should not be left on.  Is that cleaner?

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