8:23 a.m.
With this patch, it's possible to shut down guests in parallel. Parallel
startup was possible before, but this functionality was not documented
properly.
To enable parallel startup set the START_DELAY to 0.
Parallel shutdown has a configurable parameter PARALLEL_SHUTDOWN that
defines the number of machines being shut down in parallel. Enabling
this feature changes the semantics of SHUTDOWN_TIMEOUT parameter that is
applied as a cumulative timeout to shutdown all guests on a URI.
---
Diff to v1:
-changed "domains" to "guests"
-used efficient code to avoid subshells
-remove unused helper functions
-added error message when loosing track of guest in case of error
-added docs that setting of SHUTDOWN_TIMEOUT is needed with shutdown action
-added initialisation of PARALLEL_SHUTDOWN
-fixed output redirections
-fixed typo in sysconfig file
tools/libvirt-guests.init.sh | 116 +++++++++++++++++++++++++++++++++++++++---
tools/libvirt-guests.sysconf | 12 ++++-
2 files changed, 119 insertions(+), 9 deletions(-)
diff --git a/tools/libvirt-guests.init.sh b/tools/libvirt-guests.init.sh
index c867ece..141d7fa 100644
--- a/tools/libvirt-guests.init.sh
+++ b/tools/libvirt-guests.init.sh
@@ -42,6 +42,7 @@ URIS=default
ON_BOOT=start
ON_SHUTDOWN=suspend
SHUTDOWN_TIMEOUT=0
+PARALLEL_SHUTDOWN=0
START_DELAY=0
BYPASS_CACHE=0
@@ -273,6 +274,102 @@ shutdown_guest()
fi
}
+# shutdown_guest_async URI GUEST
+# Start a ACPI shutdown of GUEST on URI. This function returns after the command
+# was issued to libvirt to allow parallel shutdown.
+shutdown_guest_async()
+{
+ uri=$1
+ guest=$2
+
+ name=$(guest_name "$uri" "$guest")
+ eval_gettext "Starting shutdown on guest: \$name"
+ echo
+ retval run_virsh "$uri" shutdown "$guest" > /dev/null
+}
+
+# guest_count GUEST_LIST
+# Returns number of guests in GUEST_LIST
+guest_count()
+{
+ set -- $1
+ echo $#
+}
+
+# check_guests_shutdown URI GUESTS
+# check if shutdown is complete on guests in "GUESTS" and returns only
+# guests that are still shutting down
+check_guests_shutdown()
+{
+ uri=$1
+ guests=$2
+
+ guests_up=
+ for guest in $guests; do
+ if ! guest_is_on "$uri" "$guest" >/dev/null 2>&1;
then
+ eval_gettext "Failed to determine state of guest: \$guest. Not tracking
it anymore."
+ echo
+ continue
+ fi
+ if "$guest_running"; then
+ guests_up="$guests_up $guest"
+ fi
+ done
+ echo "$guests_up"
+}
+
+# print_guests_shutdown URI BEFORE AFTER
+# Checks for differences in the lists BEFORE and AFTER and prints
+# a shutdown complete notice for guests that have finished
+print_guests_shutdown()
+{
+ uri=$1
+ before=$2
+ after=$3
+
+ for guest in $before; do
+ case " $after " in
+ *" $guest "*) continue;;
+ esac
+
+ name=$(guest_name "$uri" "$guest")
+ eval_gettext "Shutdown of guest \$name complete."
+ echo
+ done
+}
+
+# shutdown_guests_parallel URI GUESTS
+# Shutdown guests GUESTS on machine URI in parallel
+shutdown_guests_parallel()
+{
+ uri=$1
+ guests=$2
+
+ on_shutdown=
+ timeout=$SHUTDOWN_TIMEOUT
+ while [ -n "$on_shutdown" ] || [ -n "$guests" ]; do
+ while [ -n "$guests" ] &&
+ [ $(guest_count "$on_shutdown") -lt
"$PARALLEL_SHUTDOWN" ]; do
+ set -- $guests
+ guest=$1
+ shift
+ guests=$*
+ shutdown_guest_async "$uri" "$guest"
+ on_shutdown="$on_shutdown $guest"
+ done
+ sleep 1
+ timeout=$(($timeout - 1))
+ if [ $timeout -le 0 ]; then
+ eval_gettext "Timeout expired while shutting down domains"; echo
+ RETVAL=1
+ return
+ fi
+ on_shutdown_prev=$on_shutdown
+ on_shutdown=$(check_guests_shutdown "$uri" "$on_shutdown")
+ print_guests_shutdown "$uri" "$on_shutdown_prev"
"$on_shutdown"
+ done
+}
+
# stop
# Shutdown or save guests on the configured uris
stop() {
@@ -359,13 +456,18 @@ stop() {
eval_gettext "Shutting down guests on \$uri URI..."; echo
fi
- for guest in $list; do
- if "$suspending"; then
- suspend_guest "$uri" "$guest"
- else
- shutdown_guest "$uri" "$guest"
- fi
- done
+ if [ "$PARALLEL_SHUTDOWN" -gt 1 ] &&
+ ! "$suspending"; then
+ shutdown_guests_parallel "$uri" "$list"
+ else
+ for guest in $list; do
+ if "$suspending"; then
+ suspend_guest "$uri" "$guest"
+ else
+ shutdown_guest "$uri" "$guest"
+ fi
+ done
+ fi
done <"$LISTFILE"
rm -f "$VAR_SUBSYS_LIBVIRT_GUESTS"
diff --git a/tools/libvirt-guests.sysconf b/tools/libvirt-guests.sysconf
index 9b8b64f..3e0db46 100644
--- a/tools/libvirt-guests.sysconf
+++ b/tools/libvirt-guests.sysconf
@@ -10,7 +10,8 @@
# libvirtd
#ON_BOOT=start
-# number of seconds to wait between each guest start
+# Number of seconds to wait between each guest start. Set to 0 to allow
+# parallel startup.
#START_DELAY=0
# action taken on host shutdown
@@ -23,7 +24,14 @@
# value suitable for your guests.
#ON_SHUTDOWN=suspend
-# number of seconds we're willing to wait for a guest to shut down
+# If set to non-zero, shutdown will suspend guests concurrently. Number of
+# guests on shutdown at any time will not exceed number set in this variable.
+#PARALLEL_SHUTDOWN=0
+
+# Number of seconds we're willing to wait for a guest to shut down. If parallel
+# shutdown is enabled, this timeout applies as a timeout for shutting down all
+# guests on a single URI defined in the variable URIS. This must be set to
+# a nonzero positive value if the shutdown action is requested.
#SHUTDOWN_TIMEOUT=0
# If non-zero, try to bypass the file system cache when saving and
--
1.7.3.4