Changeset 43861 in vbox for trunk/src/VBox/Devices

Timestamp:

Nov 13, 2012 10:35:55 AM (12 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

82046

Message:

Storage: Introduce new flag to skip unnecessary consistency checks in the VMDK backend while opening an image in readonly mode to speed up opening snapshots

File:

• trunk/src/VBox/Devices/Storage/DrvVD.cpp (modified) (6 diffs)

trunk/src/VBox/Devices/Storage/DrvVD.cpp

@@ -2142 +2142 @@
     bool        fDiscard = false;
     bool        fInformAboutZeroBlocks = false;
+    bool        fSkipConsistencyChecks = false;
     unsigned    iLevel = 0;
     PCFGMNODE   pCurNode = pCfg;
@@ -2159 +2160 @@
                                           "HostIPStack\0UseNewIo\0BootAcceleration\0BootAccelerationBuffer\0"
                                           "SetupMerge\0MergeSource\0MergeTarget\0BwGroup\0Type\0BlockCache\0"
-                                          "CachePath\0CacheFormat\0Discard\0InformAboutZeroBlocks\0");
+                                          "CachePath\0CacheFormat\0Discard\0InformAboutZeroBlocks\0"
+                                          "SkipConsistencyChecks\0");
         }
         else
@@ -2299 +2301 @@
                 rc = PDMDRV_SET_ERROR(pDrvIns, rc,
                                       N_("DrvVD: Configuration error: Querying \"InformAboutZeroBlocks\" as boolean failed"));
+                break;
+            }
+            rc = CFGMR3QueryBoolDef(pCurNode, "SkipConsistencyChecks", &fSkipConsistencyChecks, true);
+            if (RT_FAILURE(rc))
+            {
+                rc = PDMDRV_SET_ERROR(pDrvIns, rc,
+                                      N_("DrvVD: Configuration error: Querying \"SKipConsistencyChecks\" as boolean failed"));
                 break;
             }
@@ -2405 +2414 @@
     if (pThis->pDrvMediaAsyncPort && fUseNewIo)
         pThis->fAsyncIOSupported = true;
+
+    uint64_t tsStart = RTTimeNanoTS();
 
     unsigned iImageIdx = 0;
@@ -2603 +2614 @@
         if (fInformAboutZeroBlocks)
             uOpenFlags |= VD_OPEN_FLAGS_INFORM_ABOUT_ZERO_BLOCKS;
+        if (   (uOpenFlags & VD_OPEN_FLAGS_READONLY)
+            && fSkipConsistencyChecks)
+            uOpenFlags |= VD_OPEN_FLAGS_SKIP_CONSISTENCY_CHECKS;
 
         /* Try to open backend in async I/O mode first. */
@@ -2662 +2676 @@
         pCurNode = CFGMR3GetParent(pCurNode);
     }
+
+    LogRel(("VD: Opening the disk took %lld ns\n", RTTimeNanoTS() - tsStart));
 
     /* Open the cache image if set. */