openstack/nova
Code Issues Proposed changes

libvirt: fix DiskSmallerThanImage when block migrate ephemerals

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When block live migrate an instance with ephemerals an exception
FlavorDiskSmallerThanImage can be raised because the size used to
create the base ephemeral disk is the total size allowed by flavor
which can be greater than the size effectively requested by the
instance when spwaned.

Closes-Bug: #1628449
Change-Id: I264f5beb73d9b8ba441aec8f8a317b553a7e22c0
This commit is contained in:
Sahid Orentino Ferdjaoui 2016-09-28 07:49:45 -04:00
parent 7a9eb10d0d
commit 407e659eb9
2 changed files with 17 additions and 10 deletions
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8
nova/tests/unit/virt/libvirt/test_driver.py
View File

@ -9307,10 +9307,11 @@ class LibvirtConnTestCase(test.NoDBTestCase):
CONF.image_cache_subdirectory_name)
instance = objects.Instance(**self.test_instance)
disk_info_byname = fake_disk_info_byname(instance)
disk_info = disk_info_byname.values()
# Give the ephemeral disk a non-default name
disk_info_byname['disk.local']['backing_file'] = 'ephemeral_foo'
disk_info_byname['disk.local']['virt_disk_size'] = 1 * units.Gi
disk_info = disk_info_byname.values()
with test.nested(
mock.patch.object(libvirt_driver.libvirt_utils, 'fetch_image'),
@ -9338,8 +9339,7 @@ class LibvirtConnTestCase(test.NoDBTestCase):
verify_base_size_mock.assert_has_calls([
mock.call(root_backing, instance.flavor.root_gb * units.Gi),
mock.call(ephemeral_backing,
instance.flavor.ephemeral_gb * units.Gi)
mock.call(ephemeral_backing, 1 * units.Gi)
])
def test_create_images_and_backing_disk_info_none(self):

11
nova/virt/libvirt/driver.py
View File

@ -6608,12 +6608,19 @@ class LibvirtDriver(driver.ComputeDriver):
instance_disk,
CONF.libvirt.images_type)
if cache_name.startswith('ephemeral'):
image.cache(fetch_func=self._create_ephemeral,
# The argument 'size' is used by image.cache to
# validate disk size retrieved from cache against
# the instance disk size (should always return OK)
# and ephemeral_size is used by _create_ephemeral
# to build the image if the disk is not already
# cached.
image.cache(
fetch_func=self._create_ephemeral,
fs_label=cache_name,
os_type=instance.os_type,
filename=cache_name,
size=info['virt_disk_size'],
ephemeral_size=instance.flavor.ephemeral_gb)
ephemeral_size=info['virt_disk_size'] / units.Gi)
elif cache_name.startswith('swap'):
inst_type = instance.get_flavor()
swap_mb = inst_type.swap