[libvirt] [PATCH v2] daemon: Allow overriding NOFILES ulimit for the daemon as well

[Michal Privoznik]

One of my latest patches (d8db0f9690) created support for setting
the limit for the maximum of opened files by qemu user. However,
since libvirtd keeps one FD opened per domain (well, for qemu at least)
it will likely hit this limit on huge scenarios.
---
 daemon/libvirtd.init.in    |    7 +++++++
 daemon/libvirtd.service.in |    2 ++
 daemon/libvirtd.sysconf    |    3 +++
 daemon/libvirtd.upstart    |    5 +++++
 4 files changed, 17 insertions(+), 0 deletions(-)

diff --git a/daemon/libvirtd.init.in b/daemon/libvirtd.init.in
index 4e610cb..3c49b1f 100644
--- a/daemon/libvirtd.init.in
+++ b/daemon/libvirtd.init.in
@@ -60,6 +60,13 @@ start() {
     echo -n $"Starting $SERVICE daemon: "
     mkdir -p @localstatedir@/cache/libvirt
     rm -rf @localstatedir@/cache/libvirt/*
+
+    # LIBVIRTD_NOFILES_LIMIT from /etc/sysconfig/libvirtd is not handled
+    # automatically
+    if [ -n "$LIBVIRTD_NOFILES_LIMIT" ]; then
+        ulimit -n "$LIBVIRTD_NOFILES_LIMIT"
+    fi
+
     KRB5_KTNAME=$KRB5_KTNAME daemon --pidfile $PIDFILE --check $SERVICE $PROCESS --daemon $LIBVIRTD_CONFIG_ARGS $LIBVIRTD_ARGS
     RETVAL=$?
     echo
diff --git a/daemon/libvirtd.service.in b/daemon/libvirtd.service.in
index 9661428..8f2458a 100644
--- a/daemon/libvirtd.service.in
+++ b/daemon/libvirtd.service.in
@@ -15,6 +15,8 @@ Before=libvirt-guests.service
 EnvironmentFile=-/etc/sysconfig/libvirtd
 ExecStart=@sbindir@/libvirtd $LIBVIRTD_ARGS
 ExecReload=/bin/kill -HUP $MAINPID
+# Override the maximum number of opened files
+#LimitNOFILE=2048
 
 [Install]
 WantedBy=multi-user.target
diff --git a/daemon/libvirtd.sysconf b/daemon/libvirtd.sysconf
index ab273c8..3af1f03 100644
--- a/daemon/libvirtd.sysconf
+++ b/daemon/libvirtd.sysconf
@@ -19,3 +19,6 @@
 #QEMU_AUDIO_DRV=sdl
 #
 #SDL_AUDIODRIVER=pulse
+
+# Override the maximum number of opened files
+#LIBVIRTD_NOFILES_LIMIT=2048
diff --git a/daemon/libvirtd.upstart b/daemon/libvirtd.upstart
index f51701a..e620f41 100644
--- a/daemon/libvirtd.upstart
+++ b/daemon/libvirtd.upstart
@@ -31,6 +31,11 @@ script
         ulimit -c "$DAEMON_COREFILE_LIMIT"
     fi
 
+    # LIBVIRTD_NOFILES_LIMIT from /etc/sysconfig/libvirtd is not handled
+    # automatically
+    if [ -n "$LIBVIRTD_NOFILES_LIMIT" ]; then
+        ulimit -n "$LIBVIRTD_NOFILES_LIMIT"
+    fi
     mkdir -p /var/cache/libvirt
     rm -rf /var/cache/libvirt/*
 
-- 
1.7.3.4