On Mon, May 21, 2012 at 12:23 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> If we were sure that the kernel error was permanent, then this argument
> would be moot: the data is gone already. The scary thought here is that
> it might be a transient error, such as a not-always-repeatable kernel
> bug. In that case, zeroing the page would indeed lose data that had
> been recoverable before.
Yeah, and in fact I think that's probably not a terribly remote
scenario. Also, if you're running on dying hardware, you really do
NOT want to force the kernel to write a whole bunch of pages back to
the dying disk in the midst of trying to pg_dump it before it falls
over. You just want to read what you can of what's there now.
--
Robert Haas
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