Re: tablespace_map code cleanup

On Tue, May 12, 2020 at 2:23 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
> While looking at this, I noticed that caller (perform_base_backup) of
> do_pg_start_backup, sets the backup phase as
> PROGRESS_BASEBACKUP_PHASE_WAIT_CHECKPOINT whereas, in
> do_pg_start_backup, we do collect the information about all
> tablespaces after the checkpoint.  I am not sure if it is long enough
> that we consider having a separate phase for it.   Without your patch,
> it was covered under PROGRESS_BASEBACKUP_PHASE_ESTIMATE_BACKUP_SIZE
> phase which doesn't appear to be a bad idea.

Maybe I'm confused here, but I think the size estimation still *is*
covered under PROGRESS_BASEBACKUP_PHASE_ESTIMATE_BACKUP_SIZE. It's
just that now that happens a bit later. I'm assuming that listing the
tablespaces is pretty cheap, but sizing them is expensive, as you'd
have to iterate over all the files and stat() each one.

-- 
Robert Haas
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