Re: Making pg_rewind faster

Hi,

On Wed, Oct 15, 2025 at 7:27 AM Srinath Reddy Sadipiralla
<srinath2133(at)gmail(dot)com> wrote:

>
> TBH first it seemed to me a good coding practice for future proofing,
> then i checked if there's any place in postgres we are doing
> something similar ,then found 1 in src/include/access/gist.h
>
> typedef struct GISTDeletedPageContents
> {
> /* last xid which could see the page in a scan */
> FullTransactionId deleteXid;
> } GISTDeletedPageContents;
>

It makes more sense to me if we expect the struct or same set of arguments
to be reused in different places / want a stable API reference. I don't think
we want everything to be wrapped around a struct for functions just in case.

> ..
> thanks for updating, i have attached a diff patch on
> top of v9-0001 patch , where i tried to add more tests
> ...

Thank you for the diff! Your changes are a lot cleaner and I've included it in
the latest patch. One difference I've made is instead of additionally logging in
decide_wal_file_action

> + pg_log_debug("WAL segment \"%s\" is copied to target", fname);

I realized we are already logging the WAL segments that are copied over in
print_filemap so I've updated the test to check for that instead

> qr/pg_wal\/$corrupt_wal_seg \(COPY\)/

I also updated the error message for the last three checks.

Thanks,

--
John Hsu - Amazon Web Services