This patch optimizes unnecessary calls to the lvs command when running
gnt-cluster verify (among other operations) by caching multiple series
of lvs statements into a single operation and storing the results in
a dictionary with device paths used as keys.
Signed-off-by: Federico Morg Pareschi <m...@google.com>
---
lib/backend.py | 27 ++++++--
lib/storage/base.py | 4 +-
lib/storage/bdev.py | 94 ++++++++++++++-------------
lib/storage/drbd.py | 4 +-
lib/storage/extstorage.py | 7 +-
lib/storage/filestorage.py | 4 +-
lib/storage/gluster.py | 4 +-
test/py/ganeti.storage.bdev_unittest.py | 110 ++++++++++++++------------------
8 files changed, 132 insertions(+), 122 deletions(-)
diff --git a/lib/backend.py b/lib/backend.py
index 56b5b18..ba71fbe 100644
--- a/lib/backend.py
+++ b/lib/backend.py
@@ -3804,9 +3804,13 @@ def BlockdevGetmirrorstatusMulti(disks):
"""
result = []
+ lvs_cache = None
+ is_plain_disk = any([_CheckForPlainDisk(d) for d in disks])
+ if is_plain_disk:
+ lvs_cache = bdev.LogicalVolume._GetLvGlobalInfo()
for disk in disks:
try:
- rbd = _RecursiveFindBD(disk)
+ rbd = _RecursiveFindBD(disk, lvs_cache=lvs_cache)
if rbd is None:
result.append((False, "Can't find device %s" % disk))
continue
@@ -3823,7 +3827,22 @@ def BlockdevGetmirrorstatusMulti(disks):
return result
-def _RecursiveFindBD(disk):
+def _CheckForPlainDisk(disk, found=False):
+ """Check within a disk and its children if there is a plain disk type.
+
+ @type disk: L{objects.Disk}
+ @param disk: the disk we are checking
+ @rtype: bool
+ @return: whether or not there is a plain disk type
+
+ """
+ found |= disk.dev_type == constants.DT_PLAIN
+ if disk.children:
+ return any([_CheckForPlainDisk(d, found) for d in disk.children])
+ return found
+
+
+def _RecursiveFindBD(disk, lvs_cache=None):
"""Check if a device is activated.
If so, return information about the real device.
@@ -3838,9 +3857,9 @@ def _RecursiveFindBD(disk):
children = []
if disk.children:
for chdisk in disk.children:
- children.append(_RecursiveFindBD(chdisk))
+ children.append(_RecursiveFindBD(chdisk, lvs_cache=lvs_cache))
- return bdev.FindDevice(disk, children)
+ return bdev.FindDevice(disk, children, lvs_cache=lvs_cache)
def _OpenRealBD(disk):
diff --git a/lib/storage/base.py b/lib/storage/base.py
index dcafb41..588caf2 100644
--- a/lib/storage/base.py
+++ b/lib/storage/base.py
@@ -82,7 +82,7 @@ class BlockDev(object):
"""
# pylint: disable=W0613
- def __init__(self, unique_id, children, size, params, dyn_params, *args):
+ def __init__(self, unique_id, children, size, params, dyn_params, **kwargs):
self._children = children
self.dev_path = None
self.unique_id = unique_id
@@ -121,7 +121,7 @@ class BlockDev(object):
@classmethod
def Create(cls, unique_id, children, size, spindles, params, excl_stor,
- dyn_params, *args):
+ dyn_params, **kwargs):
"""Create the device.
If the device cannot be created, it will return None
diff --git a/lib/storage/bdev.py b/lib/storage/bdev.py
index e3a48de..2d97284 100644
--- a/lib/storage/bdev.py
+++ b/lib/storage/bdev.py
@@ -78,14 +78,14 @@ class LogicalVolume(base.BlockDev):
_INVALID_NAMES = compat.UniqueFrozenset([".", "..", "snapshot", "pvmove"])
_INVALID_SUBSTRINGS = compat.UniqueFrozenset(["_mlog", "_mimage"])
- def __init__(self, unique_id, children, size, params, dyn_params, *args):
+ def __init__(self, unique_id, children, size, params, dyn_params, **kwargs):
"""Attaches to a LV device.
The unique_id is a tuple (vg_name, lv_name)
"""
super(LogicalVolume, self).__init__(unique_id, children, size, params,
- dyn_params, *args)
+ dyn_params, **kwargs)
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
raise ValueError("Invalid configuration data %s" % str(unique_id))
self._vg_name, self._lv_name = unique_id
@@ -95,7 +95,12 @@ class LogicalVolume(base.BlockDev):
self._degraded = True
self.major = self.minor = self.pe_size = self.stripe_count = None
self.pv_names = None
- self.Attach()
+ lvs_cache = kwargs.get("lvs_cache")
+ if lvs_cache:
+ lv_info = lvs_cache.get(self.dev_path)
+ self.Attach(lv_info=lv_info)
+ else:
+ self.Attach()
@staticmethod
def _GetStdPvSize(pvs_info):
@@ -436,9 +441,9 @@ class LogicalVolume(base.BlockDev):
self._lv_name = new_name
self.dev_path = utils.PathJoin("/dev", self._vg_name, self._lv_name)
- @classmethod
- def _ParseLvInfoLine(cls, line, sep):
- """Parse one line of the lvs output used in L{_GetLvInfo}.
+ @staticmethod
+ def _ParseLvInfoLine(line, sep):
+ """Parse one line of the lvs output used in L{_GetLvGlobalInfo}.
"""
elems = line.strip().split(sep)
@@ -447,13 +452,13 @@ class LogicalVolume(base.BlockDev):
# separator to the right of the output. The PV info might be empty for
# thin volumes, so stripping off the separators might cut off the last
# empty element - do this instead.
- if len(elems) == 7 and elems[-1] == "":
+ if len(elems) == 8 and elems[-1] == "":
elems.pop()
- if len(elems) != 6:
- base.ThrowError("Can't parse LVS output, len(%s) != 6", str(elems))
+ if len(elems) != 7:
+ base.ThrowError("Can't parse LVS output, len(%s) != 7", str(elems))
- (status, major, minor, pe_size, stripes, pvs) = elems
+ (path, status, major, minor, pe_size, stripes, pvs) = elems
if len(status) < 6:
base.ThrowError("lvs lv_attr is not at least 6 characters (%s)", status)
@@ -476,43 +481,41 @@ class LogicalVolume(base.BlockDev):
pv_names = []
if pvs != "":
for pv in pvs.split(","):
- m = re.match(cls._PARSE_PV_DEV_RE, pv)
+ m = re.match(LogicalVolume._PARSE_PV_DEV_RE, pv)
if not m:
base.ThrowError("Can't parse this device list: %s", pvs)
pv_names.append(m.group(1))
- return (status, major, minor, pe_size, stripes, pv_names)
+ return (path, (status, major, minor, pe_size, stripes, pv_names))
- @classmethod
- def _GetLvInfo(cls, dev_path, _run_cmd=utils.RunCmd):
- """Get info about the given existing LV to be used.
+ @staticmethod
+ def _GetLvGlobalInfo(_run_cmd=utils.RunCmd):
+ """Obtain the current state of the existing LV disks.
+
+ @return: a dict containing the state of each disk with the disk path as key
"""
sep = "|"
result = _run_cmd(["lvs", "--noheadings", "--separator=%s" % sep,
"--units=k", "--nosuffix",
- "-olv_attr,lv_kernel_major,lv_kernel_minor,"
- "vg_extent_size,stripes,devices", dev_path])
+ "-olv_path,lv_attr,lv_kernel_major,lv_kernel_minor,"
+ "vg_extent_size,stripes,devices"])
if result.failed:
- base.ThrowError("Can't find LV %s: %s, %s",
- dev_path, result.fail_reason, result.output)
- # the output can (and will) have multiple lines for multi-segment
- # LVs, as the 'stripes' parameter is a segment one, so we take
- # only the last entry, which is the one we're interested in; note
- # that with LVM2 anyway the 'stripes' value must be constant
- # across segments, so this is a no-op actually
+ logging.warning("lvs command failed, the LV cache will be empty!")
+ logging.info("lvs failure: %r", result.stderr)
+ return {}
out = result.stdout.splitlines()
- if not out: # totally empty result? splitlines() returns at least
- # one line for any non-empty string
- base.ThrowError("Can't parse LVS output, no lines? Got '%s'", str(out))
- pv_names = set()
+ if not out:
+ logging.warning("lvs command returned an empty output, the LV cache will"
+ "be empty!")
+ return {}
+ info = {}
for line in out:
- (status, major, minor, pe_size, stripes, more_pvs) = \
- cls._ParseLvInfoLine(line, sep)
- pv_names.update(more_pvs)
- return (status, major, minor, pe_size, stripes, pv_names)
+ (key, value) = LogicalVolume._ParseLvInfoLine(line, sep)
+ info[key] = value
+ return info
- def Attach(self):
+ def Attach(self, lv_info=None):
"""Attach to an existing LV.
This method will try to see if an existing and active LV exists
@@ -521,11 +524,11 @@ class LogicalVolume(base.BlockDev):
"""
self.attached = False
- try:
+ if not lv_info:
(status, major, minor, pe_size, stripes, pv_names) = \
- self._GetLvInfo(self.dev_path)
- except errors.BlockDeviceError:
- return False
+ LogicalVolume._GetLvGlobalInfo()[self.dev_path]
+ else:
+ (status, major, minor, pe_size, stripes, pv_names) = lv_info
self.major = major
self.minor = minor
@@ -747,14 +750,14 @@ class PersistentBlockDevice(base.BlockDev):
For the time being, pathnames are required to lie under /dev.
"""
- def __init__(self, unique_id, children, size, params, dyn_params, *args):
+ def __init__(self, unique_id, children, size, params, dyn_params, **kwargs):
"""Attaches to a static block device.
The unique_id is a path under /dev.
"""
super(PersistentBlockDevice, self).__init__(unique_id, children, size,
- params, dyn_params, *args)
+ params, dyn_params, **kwargs)
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
raise ValueError("Invalid configuration data %s" % str(unique_id))
self.dev_path = unique_id[1]
@@ -803,7 +806,6 @@ class PersistentBlockDevice(base.BlockDev):
def Attach(self):
"""Attach to an existing block device.
-
"""
self.attached = False
try:
@@ -870,12 +872,12 @@ class RADOSBlockDevice(base.BlockDev):
this to be functional.
"""
- def __init__(self, unique_id, children, size, params, dyn_params, *args):
+ def __init__(self, unique_id, children, size, params, dyn_params, **kwargs):
"""Attaches to an rbd device.
"""
super(RADOSBlockDevice, self).__init__(unique_id, children, size, params,
- dyn_params, *args)
+ dyn_params, **kwargs)
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
raise ValueError("Invalid configuration data %s" % str(unique_id))
@@ -1305,7 +1307,7 @@ def _VerifyDiskParams(disk):
missing)
-def FindDevice(disk, children):
+def FindDevice(disk, children, **kwargs):
"""Search for an existing, assembled device.
This will succeed only if the device exists and is assembled, but it
@@ -1321,7 +1323,7 @@ def FindDevice(disk, children):
_VerifyDiskType(disk.dev_type)
device = DEV_MAP[disk.dev_type](disk.logical_id, children, disk.size,
disk.params, disk.dynamic_params,
- disk.name, disk.uuid)
+ name=disk.name, uuid=disk.uuid, **kwargs)
if not device.attached:
return None
return device
@@ -1344,7 +1346,7 @@ def Assemble(disk, children):
_VerifyDiskParams(disk)
device = DEV_MAP[disk.dev_type](disk.logical_id, children, disk.size,
disk.params, disk.dynamic_params,
- disk.name, disk.uuid)
+ name=disk.name, uuid=disk.uuid)
device.Assemble()
return device
@@ -1368,7 +1370,7 @@ def Create(disk, children, excl_stor):
device = DEV_MAP[disk.dev_type].Create(disk.logical_id, children, disk.size,
disk.spindles, disk.params, excl_stor,
disk.dynamic_params,
- disk.name, disk.uuid)
+ name=disk.name, uuid=disk.uuid)
return device
# Please keep this at the bottom of the file for visibility.
diff --git a/lib/storage/drbd.py b/lib/storage/drbd.py
index 5c4817b..081e96a 100644
--- a/lib/storage/drbd.py
+++ b/lib/storage/drbd.py
@@ -183,7 +183,7 @@ class DRBD8Dev(base.BlockDev):
# timeout constants
_NET_RECONFIG_TIMEOUT = 60
- def __init__(self, unique_id, children, size, params, dyn_params, *args):
+ def __init__(self, unique_id, children, size, params, dyn_params, **kwargs):
if children and children.count(None) > 0:
children = []
if len(children) not in (0, 2):
@@ -210,7 +210,7 @@ class DRBD8Dev(base.BlockDev):
logging.info("drbd%s: Ignoring unreadable meta device", self._aminor)
children = []
super(DRBD8Dev, self).__init__(unique_id, children, size, params,
- dyn_params, *args)
+ dyn_params, **kwargs)
self.major = self._DRBD_MAJOR
info = DRBD8.GetProcInfo()
diff --git a/lib/storage/extstorage.py b/lib/storage/extstorage.py
index 311662f..32f7f45 100644
--- a/lib/storage/extstorage.py
+++ b/lib/storage/extstorage.py
@@ -52,13 +52,14 @@ class ExtStorageDevice(base.BlockDev):
handling of the externally provided block devices.
"""
- def __init__(self, unique_id, children, size, params, dyn_params, *args):
+ def __init__(self, unique_id, children, size, params, dyn_params, **kwargs):
"""Attaches to an extstorage block device.
"""
super(ExtStorageDevice, self).__init__(unique_id, children, size, params,
- dyn_params, *args)
- (self.name, self.uuid) = args
+ dyn_params, **kwargs)
+ self.name = kwargs["name"]
+ self.uuid = kwargs["uuid"]
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
raise ValueError("Invalid configuration data %s" % str(unique_id))
diff --git a/lib/storage/filestorage.py b/lib/storage/filestorage.py
index 74234e8..ba89975 100644
--- a/lib/storage/filestorage.py
+++ b/lib/storage/filestorage.py
@@ -190,14 +190,14 @@ class FileStorage(base.BlockDev):
The unique_id for the file device is a (file_driver, file_path) tuple.
"""
- def __init__(self, unique_id, children, size, params, dyn_params, *args):
+ def __init__(self, unique_id, children, size, params, dyn_params, **kwargs):
"""Initalizes a file device backend.
"""
if children:
raise errors.BlockDeviceError("Invalid setup for file device")
super(FileStorage, self).__init__(unique_id, children, size, params,
- dyn_params, *args)
+ dyn_params, **kwargs)
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
raise ValueError("Invalid configuration data %s" % str(unique_id))
self.driver = unique_id[0]
diff --git a/lib/storage/gluster.py b/lib/storage/gluster.py
index 6418c9d..6aab127 100644
--- a/lib/storage/gluster.py
+++ b/lib/storage/gluster.py
@@ -293,7 +293,7 @@ class GlusterStorage(base.BlockDev):
The unique_id for the file device is a (file_driver, file_path) tuple.
"""
- def __init__(self, unique_id, children, size, params, dyn_params, *args):
+ def __init__(self, unique_id, children, size, params, dyn_params, **kwargs):
"""Initalizes a file device backend.
"""
@@ -316,7 +316,7 @@ class GlusterStorage(base.BlockDev):
self.file = None
super(GlusterStorage, self).__init__(unique_id, children, size,
- params, dyn_params, *args)
+ params, dyn_params, **kwargs)
self.Attach()
diff --git a/test/py/ganeti.storage.bdev_unittest.py
b/test/py/ganeti.storage.bdev_unittest.py
index 8b6106c..89f3b49 100755
--- a/test/py/ganeti.storage.bdev_unittest.py
+++ b/test/py/ganeti.storage.bdev_unittest.py
@@ -239,38 +239,43 @@ class TestLogicalVolume(unittest.TestCase):
def testParseLvInfoLine(self):
"""Tests for LogicalVolume._ParseLvInfoLine."""
broken_lines = [
- " toomuch#-wi-ao#253#3#4096.00#2#/dev/abc(20)",
- " -wi-ao#253#3#4096.00#/dev/abc(20)",
- " -wi-a#253#3#4096.00#2#/dev/abc(20)",
- " -wi-ao#25.3#3#4096.00#2#/dev/abc(20)",
- " -wi-ao#twenty#3#4096.00#2#/dev/abc(20)",
- " -wi-ao#253#3.1#4096.00#2#/dev/abc(20)",
- " -wi-ao#253#three#4096.00#2#/dev/abc(20)",
- " -wi-ao#253#3#four#2#/dev/abc(20)",
- " -wi-ao#253#3#4096..00#2#/dev/abc(20)",
- " -wi-ao#253#3#4096.00#2.0#/dev/abc(20)",
- " -wi-ao#253#3#4096.00#two#/dev/abc(20)",
+ " toomuch#devpath#-wi-ao#253#3#4096.00#2#/dev/abc(20)",
+ " devpath#-wi-ao#253#3#4096.00#/dev/abc(20)",
+ " devpath#-wi-a#253#3#4096.00#2#/dev/abc(20)",
+ " devpath#-wi-ao#25.3#3#4096.00#2#/dev/abc(20)",
+ " devpath#-wi-ao#twenty#3#4096.00#2#/dev/abc(20)",
+ " devpath#-wi-ao#253#3.1#4096.00#2#/dev/abc(20)",
+ " devpath#-wi-ao#253#three#4096.00#2#/dev/abc(20)",
+ " devpath#-wi-ao#253#3#four#2#/dev/abc(20)",
+ " devpath#-wi-ao#253#3#4096..00#2#/dev/abc(20)",
+ " devpath#-wi-ao#253#3#4096.00#2.0#/dev/abc(20)",
+ " devpath#-wi-ao#253#3#4096.00#two#/dev/abc(20)",
+ " devpath#-wi-ao#253#3#4096.00#2#/dev/abc20",
]
for broken in broken_lines:
self.assertRaises(errors.BlockDeviceError,
bdev.LogicalVolume._ParseLvInfoLine, broken, "#")
# Examples of good lines from "lvs":
- # -wi-ao|253|3|4096.00|2|/dev/sdb(144),/dev/sdc(0)
- # -wi-a-|253|4|4096.00|1|/dev/sdb(208)
+ #
+ # /dev/something|-wi-ao|253|3|4096.00|2|/dev/sdb(144),/dev/sdc(0)
+ # /dev/somethingelse|-wi-a-|253|4|4096.00|1|/dev/sdb(208)
true_out = [
- ("-wi-ao", 253, 3, 4096.00, 2, ["/dev/abc"]),
- ("-wi-a-", 253, 7, 4096.00, 4, ["/dev/abc"]),
- ("-ri-a-", 253, 4, 4.00, 5, ["/dev/abc", "/dev/def"]),
- ("-wc-ao", 15, 18, 4096.00, 32, ["/dev/abc", "/dev/def", "/dev/ghi0"]),
- # Physical devices might be missing with thin volumes
- ("twc-ao", 15, 18, 4096.00, 32, []),
- ]
+ ("/dev/path", ("-wi-ao", 253, 3, 4096.00, 2, ["/dev/abc"])),
+ ("/dev/path", ("-wi-a-", 253, 7, 4096.00, 4, ["/dev/abc"])),
+ ("/dev/path", ("-ri-a-", 253, 4, 4.00, 5, ["/dev/abc", "/dev/def"])),
+ ("/dev/path", ("-wc-ao", 15, 18, 4096.00, 32,
+ ["/dev/abc", "/dev/def", "/dev/ghi0"])),
+ # Physical devices might be missing with thin volumes
+ ("/dev/path", ("twc-ao", 15, 18, 4096.00, 32, [])),
+ ]
for exp in true_out:
for sep in "#;|":
- pvs = ",".join("%s(%s)" % (d, i * 12) for (i, d) in enumerate(exp[-1]))
- lvs_line = (sep.join((" %s", "%d", "%d", "%.2f", "%d", "%s")) %
- (exp[0:-1] + (pvs,)))
+ devpath = exp[0]
+ lvs = exp[1]
+ pvs = ",".join("%s(%s)" % (d, i * 12) for (i, d) in enumerate(lvs[-1]))
+ lvs_line = (sep.join((" %s", "%s", "%d", "%d", "%.2f", "%d", "%s")) %
+ ((devpath,) + lvs[0:-1] + (pvs,)))
parsed = bdev.LogicalVolume._ParseLvInfoLine(lvs_line, sep)
self.assertEqual(parsed, exp)
@@ -283,44 +288,27 @@ class TestLogicalVolume(unittest.TestCase):
return lambda cmd: utils.RunResult(exit_code, None, stdout, "", cmd,
utils.process._TIMEOUT_NONE, 5)
- def testGetLvInfo(self):
- """Tests for LogicalVolume._GetLvInfo."""
- self.assertRaises(errors.BlockDeviceError, bdev.LogicalVolume._GetLvInfo,
- "fake_path",
- _run_cmd=self._FakeRunCmd(False, "Fake error msg"))
- self.assertRaises(errors.BlockDeviceError, bdev.LogicalVolume._GetLvInfo,
- "fake_path", _run_cmd=self._FakeRunCmd(True, ""))
- self.assertRaises(errors.BlockDeviceError, bdev.LogicalVolume._GetLvInfo,
- "fake_path", _run_cmd=self._FakeRunCmd(True,
"BadStdOut"))
- good_line = " -wi-ao|253|3|4096.00|2|/dev/abc(20)"
- fake_cmd = self._FakeRunCmd(True, good_line)
- good_res = bdev.LogicalVolume._GetLvInfo("fake_path", _run_cmd=fake_cmd)
- # If the same line is repeated, the result should be the same
- for lines in [
- [good_line] * 2,
- [good_line] * 3,
- ]:
- fake_cmd = self._FakeRunCmd(True, "\n".join(lines))
- same_res = bdev.LogicalVolume._GetLvInfo("fake_path", fake_cmd)
- self.assertEqual(same_res, good_res)
-
- # Complex multi-line examples
- one_line = " -wi-ao|253|3|4096.00|2|/dev/sda(20),/dev/sdb(50),/dev/sdc(0)"
- fake_cmd = self._FakeRunCmd(True, one_line)
- one_res = bdev.LogicalVolume._GetLvInfo("fake_path", _run_cmd=fake_cmd)
- # These should give the same results
- for multi_lines in [
- (" -wi-ao|253|3|4096.00|2|/dev/sda(30),/dev/sdb(50)\n"
- " -wi-ao|253|3|4096.00|2|/dev/sdb(200),/dev/sdc(300)"),
- (" -wi-ao|253|3|4096.00|2|/dev/sda(0)\n"
- " -wi-ao|253|3|4096.00|2|/dev/sdb(20)\n"
- " -wi-ao|253|3|4096.00|2|/dev/sdc(30)"),
- (" -wi-ao|253|3|4096.00|2|/dev/sda(20)\n"
- " -wi-ao|253|3|4096.00|2|/dev/sdb(50),/dev/sdc(0)"),
- ]:
- fake_cmd = self._FakeRunCmd(True, multi_lines)
- multi_res = bdev.LogicalVolume._GetLvInfo("fake_path", _run_cmd=fake_cmd)
- self.assertEqual(multi_res, one_res)
+ def testGetLvGlobalInfo(self):
+ """Tests for LogicalVolume._GetLvGlobalInfo."""
+
+ good_lines="/dev/1|-wi-ao|253|3|4096.00|2|/dev/sda(20)\n" \
+ "/dev/2|-wi-ao|253|3|4096.00|2|/dev/sda(21)\n"
+ expected_output = {"/dev/1": ("-wi-ao", 253, 3, 4096, 2, ["/dev/sda"]),
+ "/dev/2": ("-wi-ao", 253, 3, 4096, 2, ["/dev/sda"])}
+
+ self.assertEqual({},
+ bdev.LogicalVolume._GetLvGlobalInfo(
+ _run_cmd=self._FakeRunCmd(False, "Fake error msg")))
+ self.assertEqual({},
+ bdev.LogicalVolume._GetLvGlobalInfo(
+ _run_cmd=self._FakeRunCmd(True, "")))
+ self.assertRaises(errors.BlockDeviceError,
+ bdev.LogicalVolume._GetLvGlobalInfo,
+ _run_cmd=self._FakeRunCmd(True, "BadStdOut"))
+
+ fake_cmd = self._FakeRunCmd(True, good_lines)
+ good_res = bdev.LogicalVolume._GetLvGlobalInfo(_run_cmd=fake_cmd)
+ self.assertEqual(expected_output, good_res)
@testutils.patch_object(bdev.LogicalVolume, "Attach")
def testLogicalVolumeImport(self, attach_mock):
--
2.8.0.rc3.226.g39d4020
