vm: Log changes in drive extension info

Each time drives' capacity, allocation, or physical change, log a debug log with the new values. This log will allow easy debugging when lower level component misbehave. Here is an example log when starting a VM: 2017-08-02 02:54:24,468+0300 DEBUG (periodic/0) [virt.vm] (vmId='f33a7fbc-3dab-448c-bb41-204eccee70ba') Extension info for drive sda volume 13b40805-a43b-4c0e-9a0b-0c03a2e4ecbb: BlockInfo(capacity=8589934592L, allocation=0L, physical=1073741824L) (vm:1057) The allocation value is 0, since qemu did not write anything yet to this drive. Once qemu write to the drive, we get the correct allocation: 2017-08-02 02:54:38,473+0300 DEBUG (periodic/1) [virt.vm] (vmId='f33a7fbc-3dab-448c-bb41-204eccee70ba') Extension info for drive sda volume 13b40805-a43b-4c0e-9a0b-0c03a2e4ecbb: BlockInfo(capacity=8589934592L, allocation=2490368L, physical=1073741824L) (vm:1057) Change-Id: I68701bcb1b83295f346139b2aed64b9221a4ee44 Bug-Url: https://bugzilla.redhat.com/1461536 Signed-off-by: Nir Soffer <[email protected]>
m4mnux · Aug 8, 2017 · b718903 · b718903
1 parent 8c11924
commit b718903
Show file tree

Hide file tree

Showing 2 changed files with 19 additions and 2 deletions.
diff --git a/lib/vdsm/virt/vm.py b/lib/vdsm/virt/vm.py
@@ -1111,7 +1111,14 @@ def _getExtendInfo(self, drive):
                                           replica["volumeID"])
             physical = volsize.apparentsize
 
-        return capacity, alloc, physical
+        blockinfo = vmdevices.storage.BlockInfo(capacity, alloc, physical)
+
+        if blockinfo != drive.blockinfo:
+            drive.blockinfo = blockinfo
+            self.log.debug("Extension info for drive %s volume %s: %s",
+                           drive.name, drive.volumeID, blockinfo)
+
+        return blockinfo
 
     def _shouldExtendVolume(self, drive, volumeID, capacity, alloc, physical):
         nextPhysSize = drive.getNextVolumeSize(physical, capacity)

diff --git a/lib/vdsm/virt/vmdevices/storage.py b/lib/vdsm/virt/vmdevices/storage.py
@@ -94,6 +94,13 @@ def __init__(self, path, index):
     ['uuid', 'path', 'allocation', 'index'])
 
 
+BlockInfo = collections.namedtuple("BlockInfo", [
+    "capacity",  # guest virtual size
+    "allocation",  # host allocated size (highest allocated offset)
+    "physical"  # host physical size (lv size, file size)
+])
+
+
 class Drive(core.Base):
     __slots__ = ('iface', '_path', 'readonly', 'bootOrder', 'domainID',
                  'poolID', 'imageID', 'UUID', 'volumeID', 'format',
@@ -102,7 +109,7 @@ class Drive(core.Base):
                  'volumeChain', 'baseVolumeID', 'serial', 'reqsize', 'cache',
                  'extSharedState', 'drv', 'sgio', 'GUID', 'diskReplicate',
                  '_diskType', 'hosts', 'protocol', 'auth', 'discard',
-                 'vm_custom')
+                 'vm_custom', 'blockinfo')
     VOLWM_CHUNK_SIZE = (config.getint('irs', 'volume_utilization_chunk_mb') *
                         constants.MEGAB)
     VOLWM_FREE_PCT = 100 - config.getint('irs', 'volume_utilization_percent')
@@ -217,6 +224,9 @@ def __init__(self, log, **kwargs):
         self.cache = config.get('vars', 'qemu_drive_cache')
         self.discard = kwargs.get('discard', False)
 
+        # Used for chunked drives or drives replicating to chunked replica.
+        self.blockinfo = None
+
         self._customize()
         self._setExtSharedState()