Re: Cygwin cleanup

On Wed, Nov 9, 2022 at 2:04 PM Justin Pryzby <pryzby@telsasoft.com> wrote:
> +data_sync_retry = on

Sharing with the list some clues that Justin and I figured out about
what that part is doing.  Without it, you get failures like:

  PANIC:  could not open file "pg_logical/snapshots/0-14FE6B0.snap":
No such file or directory

That's been seen before:

  https://www.postgresql.org/message-id/flat/17827.1549866683%40sss.pgh.pa.us

That thread concluded that the operating system must have a non-atomic
rename(), ie a kernel bug.  I don't know why Cygwin would display that
behaviour and our native Windows build not; maybe timing, or maybe our
own open() and rename() wrappers for Windows do something important
differently than Cygwin's open() and rename().

On reflection, that seems a bit too flimsy to have in-tree without
more investigation, which I won't have time for myself, so I'm going
to withdraw this entry.