branches/zip rb://182

Call fsync() on datafiles after a batch of pages is written to disk
even when skip_innodb_doublewrite is set.

Approved by: Heikki

buf/buf0flu.c

@@ -303,6 +303,28 @@ buf_flush_write_complete(
 	}
 }
 
+/********************************************************************//**
+Flush a batch of writes to the datafiles that have already been
+written by the OS. */
+static
+void
+buf_flush_sync_datafiles(void)
+/*==========================*/
+{
+	/* Wake possible simulated aio thread to actually post the
+	writes to the operating system */
+	os_aio_simulated_wake_handler_threads();
+
+	/* Wait that all async writes to tablespaces have been posted to
+	the OS */
+	os_aio_wait_until_no_pending_writes();
+
+	/* Now we flush the data to disk (for example, with fsync) */
+	fil_flush_file_spaces(FIL_TABLESPACE);
+
+	return;
+}
+
 /********************************************************************//**
 Flushes possible buffered writes from the doublewrite memory buffer to disk,
 and also wakes up the aio thread if simulated aio is used. It is very
@@ -320,8 +342,8 @@ buf_flush_buffered_writes(void)
 	ulint		i;
 
 	if (!srv_use_doublewrite_buf || trx_doublewrite == NULL) {
-		os_aio_simulated_wake_handler_threads();
-
+		/* Sync the writes to the disk. */
+		buf_flush_sync_datafiles();
 		return;
 	}
 
@@ -529,22 +551,10 @@ flush:
 		buf_LRU_stat_inc_io();
 	}
 
-	/* Wake possible simulated aio thread to actually post the
-	writes to the operating system */
-
-	os_aio_simulated_wake_handler_threads();
-
-	/* Wait that all async writes to tablespaces have been posted to
-	the OS */
-
-	os_aio_wait_until_no_pending_writes();
-
-	/* Now we flush the data to disk (for example, with fsync) */
-
-	fil_flush_file_spaces(FIL_TABLESPACE);
+	/* Sync the writes to the disk. */
+	buf_flush_sync_datafiles();
 
 	/* We can now reuse the doublewrite memory buffer: */
-
 	trx_doublewrite->first_free = 0;
 
 	mutex_exit(&(trx_doublewrite->mutex));