Many files:

  Merge InnoDB-3.23.50


innobase/btr/btr0btr.c:
  Merge InnoDB-3.23.50
innobase/btr/btr0cur.c:
  Merge InnoDB-3.23.50
innobase/btr/btr0sea.c:
  Merge InnoDB-3.23.50
innobase/buf/buf0buf.c:
  Merge InnoDB-3.23.50
innobase/buf/buf0flu.c:
  Merge InnoDB-3.23.50
innobase/dict/dict0dict.c:
  Merge InnoDB-3.23.50
innobase/dict/dict0load.c:
  Merge InnoDB-3.23.50
innobase/fil/fil0fil.c:
  Merge InnoDB-3.23.50
innobase/fsp/fsp0fsp.c:
  Merge InnoDB-3.23.50
innobase/include/buf0flu.h:
  Merge InnoDB-3.23.50
innobase/include/dict0dict.h:
  Merge InnoDB-3.23.50
innobase/include/fil0fil.h:
  Merge InnoDB-3.23.50
innobase/include/fsp0fsp.h:
  Merge InnoDB-3.23.50
innobase/include/log0log.h:
  Merge InnoDB-3.23.50
innobase/include/log0recv.h:
  Merge InnoDB-3.23.50
innobase/include/mem0mem.h:
  Merge InnoDB-3.23.50
innobase/include/os0file.h:
  Merge InnoDB-3.23.50
innobase/include/row0mysql.h:
  Merge InnoDB-3.23.50
innobase/include/srv0srv.h:
  Merge InnoDB-3.23.50
innobase/include/srv0start.h:
  Merge InnoDB-3.23.50
innobase/include/trx0sys.h:
  Merge InnoDB-3.23.50
innobase/include/ut0byte.h:
  Merge InnoDB-3.23.50
innobase/include/ut0rnd.h:
  Merge InnoDB-3.23.50
innobase/include/ut0ut.h:
  Merge InnoDB-3.23.50
innobase/log/log0log.c:
  Merge InnoDB-3.23.50
innobase/log/log0recv.c:
  Merge InnoDB-3.23.50
innobase/mem/mem0mem.c:
  Merge InnoDB-3.23.50
innobase/os/os0file.c:
  Merge InnoDB-3.23.50
innobase/rem/rem0cmp.c:
  Merge InnoDB-3.23.50
innobase/row/row0ins.c:
  Merge InnoDB-3.23.50
innobase/row/row0mysql.c:
  Merge InnoDB-3.23.50
innobase/row/row0sel.c:
  Merge InnoDB-3.23.50
innobase/row/row0upd.c:
  Merge InnoDB-3.23.50
innobase/srv/srv0srv.c:
  Merge InnoDB-3.23.50
innobase/srv/srv0start.c:
  Merge InnoDB-3.23.50
innobase/trx/trx0sys.c:
  Merge InnoDB-3.23.50
innobase/ut/ut0mem.c:
  Merge InnoDB-3.23.50
innobase/ut/ut0ut.c:
  Merge InnoDB-3.23.50
sql/ha_innobase.cc:
  Merge InnoDB-3.23.50
sql/ha_innobase.h:
  Merge InnoDB-3.23.50

1 files changed, 36 insertions, 0 deletions

diff --git a/innobase/trx/trx0sys.c b/innobase/trx/trx0sys.c
index b29ffb4b3bf..6c9776560bd 100644
--- a/innobase/trx/trx0sys.c
+++ b/innobase/trx/trx0sys.c
@@ -20,12 +20,43 @@ Created 3/26/1996 Heikki Tuuri
 #include "srv0srv.h"
 #include "trx0purge.h"
 #include "log0log.h"
+#include "os0file.h"
 
 /* The transaction system */
 trx_sys_t*		trx_sys 	= NULL;
 trx_doublewrite_t*	trx_doublewrite = NULL;
 
 /********************************************************************
+Determines if a page number is located inside the doublewrite buffer. */
+
+ibool
+trx_doublewrite_page_inside(
+/*========================*/
+				/* out: TRUE if the location is inside
+				the two blocks of the doublewrite buffer */
+	ulint	page_no)	/* in: page number */
+{
+	if (trx_doublewrite == NULL) {
+
+		return(FALSE);
+	}
+
+	if (page_no >= trx_doublewrite->block1
+	    && page_no < trx_doublewrite->block1
+					+ TRX_SYS_DOUBLEWRITE_BLOCK_SIZE) {
+		return(TRUE);
+	}
+
+	if (page_no >= trx_doublewrite->block2
+	    && page_no < trx_doublewrite->block2
+					+ TRX_SYS_DOUBLEWRITE_BLOCK_SIZE) {
+		return(TRUE);
+	}
+
+	return(FALSE);
+}
+
+/********************************************************************
 Creates or initialializes the doublewrite buffer at a database start. */
 static
 void
@@ -36,6 +67,11 @@ trx_doublewrite_init(
 {
 	trx_doublewrite = mem_alloc(sizeof(trx_doublewrite_t));
 
+	/* When we have the doublewrite buffer in use, we do not need to
+	call os_file_flush (Unix fsync) after every write. */
+	
+	os_do_not_call_flush_at_each_write = TRUE;
+	
 	mutex_create(&(trx_doublewrite->mutex));
 	mutex_set_level(&(trx_doublewrite->mutex), SYNC_DOUBLEWRITE);