On Thu, Mar 28, 2019 at 05:08:33PM +0100, Michael Banck wrote:
Hi,
I have rebased this patch now.
I also fixed the two issues Andres reported, namely a zeroed-out
pageheader and a random LSN. The first is caught be checking for an all-
zero-page in the way PageIsVerified() does. The second is caught by
comparing the upper 32 bits of the LSN as well and demanding that they
are equal. If the LSN is corrupted, the upper 32 bits should be wildly
different to the current checkpoint LSN.
Well, at least that is a stab at a fix; there is a window where the
upper 32 bits could legitimately be different. In order to make that as
small as possible, I update the checkpoint LSN every once in a while.
Doesn't that mean we'll report a false positive?
regards
--
Tomas Vondra http://www.2ndQuadrant.com
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