Changeset 1663:ccf5a393facd

Timestamp:

06/16/08 12:20:14 (2 months ago)

Author:

klai@…

Children:

1664:c3f9598e57b5, 1670:b68f577681e2

Branch:

default

Message:

Switch off creation of sparse file systems because they are very slow with tap:aio

Location:

src/Tycoon/Virtualization

Files:

• OSUtil.py (modified) (3 diffs)
• Resources.py (modified) (1 diff)

src/Tycoon/Virtualization/OSUtil.py

@@ -222 +222 @@
     get_dir_size = staticmethod(deferredGenerator(get_dir_size))
         
+    def grow_sparse_file_system(file_system, new_size, old_size):
+        # Write a single byte at the last seek position.
+        d = OSUtil.do(
+            '/bin/dd', 'if=/dev/zero', 'of=%s' % (file_system,),
+            'seek=%d' % (new_size - 1,), 'bs=1', 'count=1')
+        return d
+    grow_sparse_file_system = staticmethod(grow_sparse_file_system)
+
+    def grow_dense_file_system(file_system, new_size, old_size):
+        m = (new_size - old_size) / 1048576
+        seek = old_size / 1048576
+        d = OSUtil.do(
+            '/bin/dd', 'if=/dev/zero', 'of=%s' % (file_system,),
+            'seek=%d' % (seek,), 'bs=1M', 'count=%d' % (m,))
+        return d
+    grow_dense_file_system = staticmethod(grow_dense_file_system)
+
     def resize_file_system(file_system, size):
         """Resize a file system file.
@@ -227 +244 @@
         old_size = os.stat(file_system).st_size
         
-        # Round down to nearest number of KB
-        k = size / 1024
-        real_size = k * 1024
+        # Round down to nearest number of MB
+        m = size / 1048576
+        real_size = m * 1048576
         if real_size > old_size:
-            d = OSUtil.do(
-                '/bin/dd', 'if=/dev/zero', 'of=%s' % (file_system,),
-                'seek=%d' % (real_size - 1,), 'bs=1', 'count=1')
+            # Sparse file systems are faster to create, but slower to use
+            # than dense ones.
+            sparse = False
+            if sparse:
+                d = OSUtil.grow_sparse_file_system(
+                    file_system, real_size, old_size)
+            else:
+                d = OSUtil.grow_dense_file_system(
+                    file_system, real_size, old_size)
             yield d
             d = OSUtil.do('/sbin/e2fsck','-f', '-y', file_system)
@@ -242 +265 @@
             d = OSUtil.do('/sbin/e2fsck','-f', '-y', file_system)
             yield d
-            d = OSUtil.do('/sbin/resize2fs', file_system, "%dK" % (k,))
+            d = OSUtil.do('/sbin/resize2fs', file_system, "%dM" % (m,))
             yield d
             f = file(file_system, "a+")

src/Tycoon/Virtualization/Resources.py

@@ -61 +61 @@
 
     def set_last_share(self, account_name):
-        self.set_share(*((account_name,) + self.last_share[account_name]))
+        last_share = self.last_share.get(account_name)
+        if last_share != None:
+            self.set_share(*((account_name,) + last_share))
         
     def clear_shares(self):