Changeset 6472 in vbox

Timestamp:

Jan 24, 2008 8:47:39 AM (17 years ago)

Author:

vboxsync

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

27468

Message:

vdi: fill fixed-size images with zeros during creation

File:

• trunk/src/VBox/Devices/Storage/VDICore.cpp (modified) (3 diffs)

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

@@ -473 +473 @@
             goto l_create_failed;
 
-        if (    (enmType == VDI_IMAGE_TYPE_FIXED)
-            &&  (fFlags & VDI_IMAGE_FLAGS_ZERO_EXPAND))
-        {
-            /* Fill image with zeroes. */
+        if (enmType == VDI_IMAGE_TYPE_FIXED)
+        {
+            /* Fill image with zeroes. We do this for every fixed-size image since on some systems
+             * (for example Windows Vista), it takes ages to write a block near the end of a sparse
+             * file and the guest could complain about an ATA timeout. */
 
             /** @todo Starting with Linux 2.6.23, there is an fallocate() system call.
@@ -485 +486 @@
                 goto l_create_failed;
 
-            /* alloc tmp zero-filled buffer */
-            void *pvBuf = RTMemTmpAllocZ(VDIDISK_DEFAULT_BUFFER_SIZE);
+            /* Allocate a temporary zero-filled buffer. Use a bigger block size to optimize writing */
+            const size_t cbBuf = 128 * _1K;
+            void *pvBuf = RTMemTmpAllocZ(cbBuf);
             if (pvBuf)
             {
@@ -495 +497 @@
                 while (cbFill > 0)
                 {
-                    unsigned to_fill = (unsigned)RT_MIN(cbFill, VDIDISK_DEFAULT_BUFFER_SIZE);
+                    unsigned to_fill = (unsigned)RT_MIN(cbFill, cbBuf);
 
                     rc = RTFileWrite(pImage->File, pvBuf, to_fill, NULL);