Fibers 1.0.0 has a bug in run-fibers in which peer schedulers aren't destroyed -
so if you had 4 cores, 1 would be destroyed when run-fibers returned, but the
other 3 would stay around.  Each scheduler uses 3 file descriptors, so for
machines with many cores, this resource leak adds up quickly - quickly enough
that the test suite can even fail because of it.

See https://github.com/wingo/fibers/issues/36.

This fixes that.  It should be safe to destroy the peer schedulers at the given
point because the threads that could be running them are all either dead or the
current thread.

As of May 21, 2020, this bug still existed in the 1.0.0 (latest) release and in
git master.
--- a/fibers.scm	2020-05-21 18:38:06.890690154 -0500
+++ b/fibers.scm	2020-05-21 18:38:56.395686693 -0500
@@ -137,5 +137,6 @@
              (%run-fibers scheduler hz finished? affinity))
            (lambda ()
              (stop-auxiliary-threads scheduler)))))
+      (for-each destroy-scheduler (scheduler-remote-peers scheduler))
       (destroy-scheduler scheduler)
       (apply values (atomic-box-ref ret))))))

2f50cef'>refs</a><a class='active' href='/guix/log/nix/nix-daemon'>log</a><a href='/guix/tree/nix/nix-daemon?id=02b16dc57230b69d998ec6c482b06be732f50cef'>tree</a><a href='/guix/commit/nix/nix-daemon?id=02b16dc57230b69d998ec6c482b06be732f50cef'>commit</a><a href='/guix/diff/nix/nix-daemon?id=02b16dc57230b69d998ec6c482b06be732f50cef'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/nix/nix-daemon'>
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r</th></tr>
<tr><td><span title='2023-08-21 16:16:47 +0200'>2023-08-21</span></td><td><a href='/guix/commit/tests/graph.scm?id=df2117b8e0e9a35ef8be7f122a783190cafed669'>tests: Adjust 'node-back-edges' test for 'bag' to system-dependent glibc.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes a regression introduced in
560cb51e7b37e2c6f6fe4b72a3781185c57fdf83, which would lead this test on
x86_64-linux to return a DIFF with two packages, nhc98 and dev86 (both
have #:system "i686-linux" and thus depend on a different glibc object;
why other system-specific packages such as 'wine' aren't reported is
unclear).

* tests/graph.scm ("node-transitive-edges + node-back-edges"): Use
'test-equal'.  Define 'system-specific?' and use it.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-04-07 17:53:37 +0200'>2023-04-07</span></td><td><a href='/guix/commit/tests/graph.scm?id=acdb42e5d09a504d521d8b632c2c4a66d70f94e4'>gnu: Purge pre-1.3.0 deprecated packages.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bioinformatics.scm (deeptools): Remove variable.
* gnu/packages/efi.scm (efi_analyzer): Ditto.
* gnu/packages/guile.scm (guile-2.2/bug-fix, guile-json): Ditto.
* gnu/packages/image.scm (libjpeg): Ditto.
* gnu/packages/kde.scm (kdevplatform): Ditto
* gnu/packages/linphone.scm (linphoneqt): Ditto.
* gnu/packages/maths.scm (blis-sandybridge, blis-haswell, blis-knl): Ditto.
* gnu/packages/mpi.scm (hwloc-2.0): Ditto.
* gnu/packages/music.scm (python-abjad, zlfo): Ditto.
* gnu/packages/perl.scm (perl-base, perl-parent): Ditto.
* gnu/packages/tryton.scm (python-trytond): Ditto.
* gnu/packages/video.scm (gnome-mpv): Ditto.
* tests/graph.scm: Use guile-json-1.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Bruno Victal</td></tr>
<tr><td><span title='2022-10-22 01:46:55 +0200'>2022-10-22</span></td><td><a href='/guix/commit/tests/graph.scm?id=a3619079f95213c4f983e69210ed12b38fd31022'>Remove now unnecessary uses of (guix grafts).</a><span class='msg-avail'>...<span class='msg-tooltip'>These modules would use (guix grafts) just to access '%graft?' and
related bindings, which are now in (guix store).

* gnu/ci.scm,
guix/gexp.scm,
guix/lint.scm,
guix/scripts.scm,
guix/scripts/archive.scm,
guix/scripts/build.scm,
guix/scripts/challenge.scm,
guix/scripts/deploy.scm,
guix/scripts/environment.scm,
guix/scripts/home.scm,
guix/scripts/pack.scm,
guix/scripts/package.scm,
guix/scripts/pull.scm,
guix/scripts/size.scm,
guix/scripts/system.scm,
guix/scripts/weather.scm,
tests/builders.scm,
tests/channels.scm,
tests/cpan.scm,
tests/derivations.scm,
tests/gexp.scm,
tests/graph.scm,
tests/guix-daemon.sh,
tests/monads.scm,
tests/pack.scm,
tests/packages.scm,
tests/profiles.scm,
tests/system.scm: Remove #:use-module (guix grafts).
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-07-01 23:29:16 +0200'>2022-07-01</span></td><td><a href='/guix/commit/tests/graph.scm?id=bee2c369fa2a3d51e6a1218d1b1a0ee86528674a'>tests: Adjust 'guix graph' test to latest OCaml changes.</a><span class='msg-avail'>...<span class='msg-tooltip'>* tests/graph.scm ("reverse bag DAG"): Adjust to latest OCaml changes by
looking at dune/ocaml-camomile/ocaml-utop.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-02-05 08:02:30 +0100'>2022-02-05</span></td><td><a href='/guix/commit/tests/graph.scm?id=45082b9a8c12af285f4386538fc7acc4668cb11c'>tests: Assert that cyclic graphs can be produced.</a><span class='msg-avail'>...<span class='msg-tooltip'>* tests/graph.scm ("package DAG, oops it was a cycle"): New test.
</span></span></td><td>Liliana Marie Prikler</td></tr>
<tr><td><span title='2021-09-21 15:15:52 +0200'>2021-09-21</span></td><td><a href='/guix/commit/tests/graph.scm?id=5b32ad4f6f555d305659cee825879df075b06331'>graph: Add '--max-depth'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/graph.scm (export-graph): Add #:max-depth and honor it, adding
'depths' argument to 'loop'.
* guix/scripts/graph.scm (%options, show-help): Add '--max-depth'.
(%default-options): Add 'max-depth'.
(guix-graph): Pass #:max-depth to 'export-graph'.
* tests/graph.scm ("package DAG, limited depth"): New test.
* doc/guix.texi (Invoking guix graph): Document it.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-10-20 16:30:15 +0200'>2020-10-20</span></td><td><a href='/guix/commit/tests/graph.scm?id=a9fd59dbd2d32e08c9479ac026b99b5c1dbbb0db'>graph: Adjust test for recent OCaml changes.</a><span class='msg-avail'>...<span class='msg-tooltip'>This is a followup to 339177956affdc471832750a3805b74356487e93.

* tests/graph.scm ("reverse bag DAG"): Look for "ocaml4.07-dune" rather
than "dune".
</span></span></td><td>Ludovic Courtès</td></tr>