Many files:

  Remove potential starvation of a full log buffer flush: only flush up to the lsn which was the largest at the time when we requested the full log buffer flush
os0sync.h, os0sync.c:
  Fix a bug in os_event on Unix: even though we signaled the event, some threads could continue waiting if the event became nonsignaled quickly again; this made group commit less efficient than it should be


innobase/os/os0sync.c:
  Fix a bug in os_event on Unix: even though we signaled the event, some threads could continue waiting if the event became nonsignaled quickly again; this made group commit less efficient than it should be
innobase/include/os0sync.h:
  Fix a bug in os_event on Unix: even though we signaled the event, some threads could continue waiting if the event became nonsignaled quickly again; this made group commit less efficient than it should be
innobase/log/log0log.c:
  Remove potential starvation of a full log buffer flush: only flush up to the lsn which was the largest at the time when we requested the full log buffer flush
innobase/include/log0log.h:
  Remove potential starvation of a full log buffer flush: only flush up to the lsn which was the largest at the time when we requested the full log buffer flush
innobase/srv/srv0srv.c:
  Remove potential starvation of a full log buffer flush: only flush up to the lsn which was the largest at the time when we requested the full log buffer flush
innobase/row/row0mysql.c:
  Remove potential starvation of a full log buffer flush: only flush up to the lsn which was the largest at the time when we requested the full log buffer flush
innobase/trx/trx0trx.c:
  Remove potential starvation of a full log buffer flush: only flush up to the lsn which was the largest at the time when we requested the full log buffer flush
sql/ha_innodb.cc:
  Remove potential starvation of a full log buffer flush: only flush up to the lsn which was the largest at the time when we requested the full log buffer flush
innobase/btr/btr0btr.c:
  Remove potential starvation of a full log buffer flush: only flush up to the lsn which was the largest at the time when we requested the full log buffer flush

1 files changed, 12 insertions, 3 deletions

diff --git a/innobase/os/os0sync.c b/innobase/os/os0sync.c
index bf5fc57bf57..827d68501db 100644
--- a/innobase/os/os0sync.c
+++ b/innobase/os/os0sync.c
@@ -143,6 +143,7 @@ os_event_create(
 	ut_a(0 == pthread_cond_init(&(event->cond_var), NULL));
 #endif
 	event->is_set = FALSE;
+	event->signal_count = 0;
 #endif /* __WIN__ */
 
         /* Put to the list of events */
@@ -218,6 +219,7 @@ os_event_set(
 		/* Do nothing */
 	} else {
 		event->is_set = TRUE;
+		event->signal_count += 1;
 		ut_a(0 == pthread_cond_broadcast(&(event->cond_var)));
 	}
 
@@ -310,9 +312,15 @@ os_event_wait(
 	        os_thread_exit(NULL);
 	}
 #else
+	ib_longlong	old_signal_count;
+
 	os_fast_mutex_lock(&(event->os_mutex));
+
+	old_signal_count = event->signal_count;
 loop:
-	if (event->is_set == TRUE) {
+	if (event->is_set == TRUE
+            || event->signal_count != old_signal_count) {
+
 		os_fast_mutex_unlock(&(event->os_mutex));
 
 		if (srv_shutdown_state == SRV_SHUTDOWN_EXIT_THREADS) {
@@ -326,8 +334,9 @@ loop:
 
 	pthread_cond_wait(&(event->cond_var), &(event->os_mutex));
 
-	/* Solaris manual said that spurious wakeups may occur: we have
-	to check the 'is_set' variable again */
+	/* Solaris manual said that spurious wakeups may occur: we have to
+	check if the event really has been signaled after we came here to
+	wait */
 
 	goto loop;
 #endif