Re: corrupt pages detected by enabling checksums

On Mon, May 6, 2013 at 5:04 PM, Jeff Davis <pgsql@j-davis.com> wrote:
> On Mon, 2013-05-06 at 15:31 -0400, Robert Haas wrote:
>> On Wed, May 1, 2013 at 3:04 PM, Jeff Davis <pgsql@j-davis.com> wrote:
>> > Regardless, you have a reasonable claim that my patch had effects that
>> > were not necessary. I have attached a draft patch to remedy that. Only
>> > rudimentary testing was done.
>>
>> This looks reasonable to me.
>
> Can you please explain the scenario that loses many VM bits at once
> during a crash, and results in a bunch of already-all-visible heap pages
> being dirtied for no reason?

Hmm.  Rereading your last email, I see your point: since we now have
HEAP_XLOG_VISIBLE, this is much less of an issue than it would have
been before.  I'm still not convinced that simplifying that code is a
good idea, but maybe it doesn't really hurt us much in practice.

-- 
Robert Haas
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