From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?UTF-8?Q?Court=C3=A8s?=)
Subject: bug#30644: Cuirass runs out of build users
Date: Sun, 11 Mar 2018 22:43:48 +0100
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To: Danny Milosavljevic <dannym@scratchpost.org>
Cc: 30644@debbugs.gnu.org

Hi,

Danny Milosavljevic <dannym@scratchpost.org> skribis:

> On Thu, 08 Mar 2018 13:01:01 +0100
> ludo@gnu.org (Ludovic Court=C3=A8s) wrote:
>
>> So what=E2=80=99s your take on this?
>
> sqlite has a sqlite-unlock-notify.  We should wrap it and use it when we =
get the
> "locked" error code.
>
> We should also enable extended error codes https://sqlite.org/c3ref/exten=
ded_result_codes.html .
>
> See also https://sqlite.org/unlock_notify.html for a blocking version of =
_step (to the right).

Interesting.

> Do we want cuirass to block until the lock is available?

The POSIX thread itself should not block.  Rather the fiber should yield
to other fibers.

So we could do the blocking-step within =E2=80=98non-blocking=E2=80=99 bloc=
k as defined
in (cuirass utils), though =E2=80=98non-blocking=E2=80=99 as currently impl=
emented is a
bit expensive.

Or we could simply poll: catch those exceptions and try again later.  If
this is rare enough, as seems to be the case, that might be an
acceptable approach.

Thoughts?

Ludo=E2=80=99.