Re: Online enabling of checksums

Hi,

On Mon, Mar 05, 2018 at 11:09:02AM +0100, Magnus Hagander wrote:
> On Mon, Mar 5, 2018 at 10:43 AM, Michael Banck <michael.banck@credativ.de>
> wrote:
> > I still find that confusing, but maybe it's just me. I thought the one
> > in the pageheader is the "expected" checksum, and we compare the "found"
> > or "computed/calculated" (in the page itself) against it.
> >
> > I had the same conversation with an external tool author, by the way:
> 
> Maybe we should just say "on disk" for the one that's on disk, would that
> break the confusion? So "calculated %X, found %X on disk"?

I found that there is a precedent in bufpage.c:

|        ereport(WARNING,
|                (ERRCODE_DATA_CORRUPTED,
|                 errmsg("page verification failed, calculated checksum %u but expected %u",
|                        checksum, p->pd_checksum)));

apart from the fact that it doesn't print out the hex value (which I
find strange), it sounds like a sensible message to me. But "found %X on
disk" would work as well I guess.


Michael

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