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))))))

680369d118c2aa9f7bacff4'>refs</a><a class='active' href='/guix/log/gnu/services/avahi.scm'>log</a><a href='/guix/tree/gnu/services/avahi.scm?id=3d2ce30f6b4b505c9680369d118c2aa9f7bacff4'>tree</a><a href='/guix/commit/gnu/services/avahi.scm?id=3d2ce30f6b4b505c9680369d118c2aa9f7bacff4'>commit</a><a href='/guix/diff/gnu/services/avahi.scm?id=3d2ce30f6b4b505c9680369d118c2aa9f7bacff4'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/services/avahi.scm'>
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<div class='path'>path: <a href='/guix/log/?id=3d2ce30f6b4b505c9680369d118c2aa9f7bacff4'>root</a>/<a href='/guix/log/gnu?id=3d2ce30f6b4b505c9680369d118c2aa9f7bacff4'>gnu</a>/<a href='/guix/log/gnu/services?id=3d2ce30f6b4b505c9680369d118c2aa9f7bacff4'>services</a>/<a href='/guix/log/gnu/services/avahi.scm?id=3d2ce30f6b4b505c9680369d118c2aa9f7bacff4'>avahi.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/services/avahi.scm?id=3d2ce30f6b4b505c9680369d118c2aa9f7bacff4&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-11-18 15:44:39 +0100'>2022-11-18</span></td><td><a href='/guix/commit/gnu/services/avahi.scm?id=8d9647d8a77a67013c48166561134d92b5224264'>services: Add Shepherd 'configuration' action to various services.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/avahi.scm (avahi-shepherd-service): Add 'actions' field.
* gnu/services/base.scm (nscd-actions): Add call to
'shepherd-configuration-action'.
* gnu/services/desktop.scm (upower-shepherd-service): Add 'actions'
field.
(elogind-shepherd-service): Likewise.
* gnu/services/dict.scm (dicod-shepherd-service): Likewise.
* gnu/services/networking.scm (openntpd-shepherd-service): Likewise.
(tor-shepherd-service): Likewise.
* gnu/services/ssh.scm (openssh-shepherd-service): Likewise.
* gnu/services/web.scm (nginx-shepherd-service): Likewise.
* gnu/services/xorg.scm (gdm-shepherd-service): Likewise.
* gnu/tests/base.scm (run-basic-test)["nscd configuration action"]: New
test.
* doc/guix.texi (Services): Document it.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-11-30 01:08:55 +0100'>2021-11-30</span></td><td><a href='/guix/commit/gnu/services/avahi.scm?id=892f1b7273d57b25940700877a02618fe826cc08'>services: Accept &lt;inferior-package&gt;s in lieu of &lt;package&gt;s.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/authentication.scm (fprintd-configuration)
(nslcd-configuration): Substitute file-like objects for package ones.
* gnu/services/cgit.scm (cgit-configuration, opaque-cgit-configuration):
Likewise.
* gnu/services/cups.scm (package-list?, cups-configuration): Likewise.
* gnu/services/dns.scm (verify-knot-configuration)
(ddclient-configuration): Likewise.
* gnu/services/docker.scm (docker-configuration): Likewise.
* gnu/services/file-sharing.scm (transmission-daemon-configuration): Likewise.
* gnu/services/getmail.scm (getmail-configuration): Likewise.
* gnu/services/mail.scm (dovecot-configuration)
(opaque-dovecot-configuration): Likewise.
* gnu/services/messaging.scm (prosody-configuration)
(opaque-prosody-configuration): Likewise.
* gnu/services/monitoring.scm (zabbix-server-configuration)
(zabbix-agent-configuration): Likewise.
* gnu/services/networking.scm (opendht-configuration): Likewise.
* gnu/services/pm.scm (tlp-configuration): Likewise.
* gnu/services/telephony.scm (jami-configuration): Likewise.
* gnu/services/virtualization.scm (libvirt-configuration)
(qemu-guest-agent-configuration): Likewise.
* gnu/services/vpn.scm (openvpn-client-configuration): Likewise.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2021-06-14 18:35:17 +0200'>2021-06-14</span></td><td><a href='/guix/commit/gnu/services/avahi.scm?id=f70c3429ed0064eb4554722b4a60031385fd6785'>services: Remove deprecated service procedures.</a><span class='msg-avail'>...<span class='msg-tooltip'>These service procedures were deprecated in January 2019, for instance
in commit 65a67bf711b14bc7200f6730c0f173375ca12974.

* gnu/services/avahi.scm (avahi-service): Remove.
* gnu/services/base.scm (console-keymap, guix-service)
(guix-publish-service, gpm-service, urandom-seed-service): Remove.
* gnu/services/desktop.scm (upower-service, colord-service): Remove.
* gnu/services/mcron.scm (mcron-service): Remove.
* gnu/services/messaging.scm (bitlbee-service): Remove.
* gnu/services/networking.scm (dhcp-client-service, ntp-service)
(tor-service): Remove.
* gnu/services/xorg.scm (slim-service, gdm-service): Remove.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-12-09 14:13:32 +0100'>2020-12-09</span></td><td><a href='/guix/commit/gnu/services/avahi.scm?id=59a6780f70e138a515dfe9c3b5b5399dbd91c228'>services: avahi: Depend on 'user-processes'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/avahi.scm (avahi-shepherd-service): Add 'user-processes'
to 'requirement'.
</span></span></td><td>Ludovic Courtès</td></tr>