core: make GC more aggressive

Since we should allow registering/unregistering transient units with the
same name in a tight-loop, we need to make the GC more aggressive, so
that dead units are cleaned up immediately instead of later.

hence, execute the GC sweep on every event loop iteration and clean up
units. This of course, means we need to be careful with adding units to
the GC queue, which we already are since we execute check_gc() of each
unit type already when adding something to the queue.

1 files changed, 6 insertions, 15 deletions

diff --git a/src/core/manager.c b/src/core/manager.c
index 080561b5d1..6128194427 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -72,9 +72,6 @@
 #include "efivars.h"
 #include "env-util.h"
 
-/* As soon as 16 units are in our GC queue, make sure to run a gc sweep */
-#define GC_QUEUE_ENTRIES_MAX 16
-
 /* As soon as 5s passed since a unit was added to our GC queue, make sure to run a gc sweep */
 #define GC_QUEUE_USEC_MAX (10*USEC_PER_SEC)
 
@@ -604,12 +601,7 @@ static unsigned manager_dispatch_gc_queue(Manager *m) {
 
         assert(m);
 
-        if ((m->n_in_gc_queue < GC_QUEUE_ENTRIES_MAX) &&
-            (m->gc_queue_timestamp <= 0 ||
-             (m->gc_queue_timestamp + GC_QUEUE_USEC_MAX) > now(CLOCK_MONOTONIC)))
-                return 0;
-
-        log_debug("Running GC...");
+        /* log_debug("Running GC..."); */
 
         m->gc_marker += _GC_OFFSET_MAX;
         if (m->gc_marker + _GC_OFFSET_MAX <= _GC_OFFSET_MAX)
@@ -636,7 +628,6 @@ static unsigned manager_dispatch_gc_queue(Manager *m) {
         }
 
         m->n_in_gc_queue = 0;
-        m->gc_queue_timestamp = 0;
 
         return n;
 }
@@ -1733,19 +1724,19 @@ int manager_loop(Manager *m) {
                 if (manager_dispatch_load_queue(m) > 0)
                         continue;
 
-                if (manager_dispatch_run_queue(m) > 0)
+                if (manager_dispatch_gc_queue(m) > 0)
                         continue;
 
-                if (bus_dispatch(m) > 0)
+                if (manager_dispatch_cleanup_queue(m) > 0)
                         continue;
 
-                if (manager_dispatch_cleanup_queue(m) > 0)
+                if (manager_dispatch_cgroup_queue(m) > 0)
                         continue;
 
-                if (manager_dispatch_gc_queue(m) > 0)
+                if (manager_dispatch_run_queue(m) > 0)
                         continue;
 
-                if (manager_dispatch_cgroup_queue(m) > 0)
+                if (bus_dispatch(m) > 0)
                         continue;
 
                 if (manager_dispatch_dbus_queue(m) > 0)