Re: Use of rsync for data directory copying

Bruce,

* Bruce Momjian (bruce(at)momjian(dot)us) wrote:
> If two writes happens in the middle of a file in the same second, it
> seems one might be missed. Yes, I suppose the WAL does fix that during
> replay, though if both servers were shut down cleanly, WAL would not be
> replayed.
>
> If you using it for a hot backup, and WAL would clean that up.

Right... If it's hot backup, then WAL will fix it; if it's done after a
clean shut-down, nothing should be writing to those files (much less
multiple writes in the same second), so checksum shouldn't be
necessary...

If you're doing rsync w/o doing pg_start_backup/pg_stop_backup, that's
not likely to work even *with* --checksum..

So, can you explain which case you're specifically worried about?

Thanks,

Stephen