Re: sqlite3

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: emacs-devel@gnu.org
> Date: Fri, 17 Dec 2021 10:31:25 +0100
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > If you are sure the second session already exited, then my hand-waving
> > doesn't hold water.
> 
> I thought I was pretty sure, and...  today I can't reproduce the problem
> at all.  😐 It was 100% reproducible yesterday, but not today.  (And I
> reverted the change I made to handle the problem.)
> 
> OK, I ran the tests a whole bunch of times now, and it failed once, so
> the problem is still present, but hard to reproduce.  I'll keep poking
> at it, but I probably won't have time to continue today.

Is that multi-test-files-simple?  If so, it almost always fails here
today:

  Test multi-test-files-simple condition:
      (ert-test-failed
       ((should
         (=
          (multisession-value sfoo)
          2))
        :form
        (= 1 2)
        :value nil))

Which sounds like a problem different from what you saw?

Adding (sleep-for 3) after call-process doesn't entirely fix the
problem, although it becomes more rare.

I've installed a change in multisession.el that makes the problem much
more rare by forcing 'fsync' when we close the value file.  The
problem is not yet gone entirely, though: it happens with about 25%
probability here.  I think it could be related to the fact that
'rename-file' is not an atomic operation on MS-Windows. But that's a
wild guess, I have no basis for it.