diff --git a/src/core/iomgr/alarm.c b/src/core/iomgr/alarm.c
index 5b80368e3a2..cab7c17d801 100644
--- a/src/core/iomgr/alarm.c
+++ b/src/core/iomgr/alarm.c
@@ -335,8 +335,7 @@ static int run_some_expired_alarms(gpr_mu *drop_mu, gpr_timespec now,
 
     gpr_mu_unlock(&g_mu);
     gpr_mu_unlock(&g_checker_mu);
-  } else if (next) {
-    gpr_mu_lock(&g_mu);
+  } else if (next && gpr_mu_trylock(&g_mu)) {
     *next = gpr_time_min(*next, g_shard_queue[0]->min_deadline);
     gpr_mu_unlock(&g_mu);
   }
diff --git a/src/core/iomgr/alarm_internal.h b/src/core/iomgr/alarm_internal.h
index 5c6b869302e..8503292fd1a 100644
--- a/src/core/iomgr/alarm_internal.h
+++ b/src/core/iomgr/alarm_internal.h
@@ -39,6 +39,15 @@
 
 /* iomgr internal api for dealing with alarms */
 
+/* Check for alarms to be run, and run them. 
+   Return non zero if alarm callbacks were executed.
+   Drops drop_mu if it is non-null before executing callbacks.
+   If next is non-null, TRY to update *next with the next running alarm
+   IF that alarm occurs before *next current value.
+   *next is never guaranteed to be updated on any given execution; however,
+   with high probability at least one thread in the system will see an update
+   at any time slice. */
+
 int grpc_alarm_check(gpr_mu *drop_mu, gpr_timespec now, gpr_timespec *next);
 
 void grpc_alarm_list_init(gpr_timespec now);