Re: Add information to rm_redo_error_callback()

On Tue, 11 Aug 2020 at 15:30, Michael Paquier <michael(at)paquier(dot)xyz> wrote:
>
> On Tue, Aug 11, 2020 at 02:45:50PM +0900, Masahiko Sawada wrote:
> > Thank you for updating the patch!
> >
> > The patch looks good to me. I've set this patch as Ready for Committer.
>
> + for (block_id = 0; block_id <= record->max_block_id; block_id++)
> + {
> + RelFileNode rnode;
> + ForkNumber forknum;
> + BlockNumber blknum;
>
> Doesn't this potentially create duplicate information in some of the
> RM's desc() callbacks, and are we sure that the information provided
> is worth having for all the RMs? As one example, gin_desc() looks at
> some of the block information, so there are overlaps.

Yeah, there is duplicate information in some RMs. I thought that we
can change individual RM’s desc() functions to output the block
information but as long as I see the pg_waldump outputs these are not
annoying to me and many of RM’s desc() doesn’t show the block
information.

> It may be
> worth thinking about showing more information for has_image and
> apply_image if a block is in_use?

Yes. I’m okay with adding information for has_image and apply_image
but IMHO I'm not sure how these shown in errcontext would help. If an
error related to has_image or apply_image happens, errmsg should show
something detailed information about FPI.

Regards,

--
Masahiko Sawada http://www.2ndQuadrant.com/
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