openstack/glance_store
Code Issues Proposed changes

Filesystem driver: add chunk size config option

Browse Source 
At the moment, the filesystem driver uses a hardcoded 64 KB chunk
size, used when reading/writing image files.

This can be extremely inefficient, especially when file shares are
used.

For this reason, this change will make it configurable.

DocImpact

Change-Id: I1559c03308d36ecf9305c7a72ad658ecd1f2dc76
Closes-Bug: #1792869
This commit is contained in:
Lucian Petrut 2018-09-13 14:17:54 +03:00
parent 11db636c34
commit ea1cad2bed
5 changed files with 51 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
glance_store/_drivers/filesystem.py
View File

@ -148,6 +148,23 @@ Possible values:
Related options:
* None
"""),
cfg.IntOpt('filesystem_store_chunk_size',
default=64 * units.Ki,
min=1,
help="""
Chunk size, in bytes.
The chunk size used when reading or writing image files. Raising this value
may improve the throughput but it may also slightly increase the memory usage
when handling a large number of requests.
Possible Values:
* Any positive integer value
Related options:
* None
""")]
MULTI_FILESYSTEM_METADATA_SCHEMA = {
@ -243,8 +260,6 @@ class Store(glance_store.driver.Store):
capabilities.BitMasks.WRITE_ACCESS |
capabilities.BitMasks.DRIVER_REUSABLE)
OPTIONS = _FILESYSTEM_CONFIGS
READ_CHUNKSIZE = 64 * units.Ki
WRITE_CHUNKSIZE = READ_CHUNKSIZE
FILESYSTEM_STORE_METADATA = None
def get_schemes(self):
@ -384,19 +399,18 @@ class Store(glance_store.driver.Store):
itself, it should raise `exceptions.BadStoreConfiguration`
"""
if self.backend_group:
fdir = getattr(
self.conf, self.backend_group).filesystem_store_datadir
fdirs = getattr(
self.conf, self.backend_group).filesystem_store_datadirs
fstore_perm = getattr(
self.conf, self.backend_group).filesystem_store_file_perm
meta_file = getattr(
self.conf, self.backend_group).filesystem_store_metadata_file
store_conf = getattr(self.conf, self.backend_group)
else:
fdir = self.conf.glance_store.filesystem_store_datadir
fdirs = self.conf.glance_store.filesystem_store_datadirs
fstore_perm = self.conf.glance_store.filesystem_store_file_perm
meta_file = self.conf.glance_store.filesystem_store_metadata_file
store_conf = self.conf.glance_store
fdir = store_conf.filesystem_store_datadir
fdirs = store_conf.filesystem_store_datadirs
fstore_perm = store_conf.filesystem_store_file_perm
meta_file = store_conf.filesystem_store_metadata_file
self.chunk_size = store_conf.filesystem_store_chunk_size
self.READ_CHUNKSIZE = self.chunk_size
self.WRITE_CHUNKSIZE = self.READ_CHUNKSIZE
if not (fdir or fdirs):
reason = (_("Specify at least 'filesystem_store_datadir' or "

24
glance_store/tests/unit/test_filesystem_store.py
View File

@ -43,21 +43,15 @@ class TestStore(base.StoreBaseTest,
def setUp(self):
"""Establish a clean test environment."""
super(TestStore, self).setUp()
self.orig_chunksize = filesystem.Store.READ_CHUNKSIZE
filesystem.Store.READ_CHUNKSIZE = 10
self.store = filesystem.Store(self.conf)
self.config(filesystem_store_datadir=self.test_dir,
filesystem_store_chunk_size=10,
stores=['glance.store.filesystem.Store'],
group="glance_store")
self.store.configure()
self.register_store_schemes(self.store, 'file')
self.hash_algo = 'sha256'
def tearDown(self):
"""Clear the test environment."""
super(TestStore, self).tearDown()
filesystem.ChunkedFile.CHUNKSIZE = self.orig_chunksize
def _create_metadata_json_file(self, metadata):
expected_image_id = str(uuid.uuid4())
jsonfilename = os.path.join(self.test_dir,
@ -185,7 +179,10 @@ class TestStore(base.StoreBaseTest,
def test_add_with_verifier(self):
"""Test that 'verifier.update' is called when verifier is provided."""
verifier = mock.MagicMock(name='mock_verifier')
self.store.chunk_size = units.Ki
self.config(filesystem_store_chunk_size=units.Ki,
group='glance_store')
self.store.configure()
image_id = str(uuid.uuid4())
file_size = units.Ki # 1K
file_contents = b"*" * file_size
@ -741,3 +738,14 @@ class TestStore(base.StoreBaseTest,
mode = os.stat(expected_location[len('file:/'):])[stat.ST_MODE]
perm = int(str(self.conf.glance_store.filesystem_store_file_perm), 8)
self.assertEqual(perm, stat.S_IMODE(mode))
def test_configure_add_chunk_size(self):
# This definitely won't be the default
chunk_size = units.Gi
self.config(filesystem_store_chunk_size=chunk_size,
group="glance_store")
self.store.configure_add()
self.assertEqual(chunk_size, self.store.chunk_size)
self.assertEqual(chunk_size, self.store.READ_CHUNKSIZE)
self.assertEqual(chunk_size, self.store.WRITE_CHUNKSIZE)

8
glance_store/tests/unit/test_multistore_filesystem.py
View File

@ -70,19 +70,13 @@ class TestMultiStore(base.MultiStoreBaseTest,
self.test_dir = self.useFixture(fixtures.TempDir()).path
self.addCleanup(self.conf.reset)
self.orig_chunksize = filesystem.Store.READ_CHUNKSIZE
filesystem.Store.READ_CHUNKSIZE = 10
self.store = filesystem.Store(self.conf, backend='file1')
self.config(filesystem_store_datadir=self.test_dir,
filesystem_store_chunk_size=10,
group="file1")
self.store.configure()
self.register_store_backend_schemes(self.store, 'file', 'file1')
def tearDown(self):
"""Clear the test environment."""
super(TestMultiStore, self).tearDown()
filesystem.ChunkedFile.CHUNKSIZE = self.orig_chunksize
def _create_metadata_json_file(self, metadata):
expected_image_id = str(uuid.uuid4())
jsonfilename = os.path.join(self.test_dir,

1
glance_store/tests/unit/test_opts.py
View File

@ -85,6 +85,7 @@ class OptsTestCase(base.StoreBaseTest):
'cinder_volume_type',
'default_swift_reference',
'https_insecure',
'filesystem_store_chunk_size',
'filesystem_store_datadir',
'filesystem_store_datadirs',
'filesystem_store_file_perm',

5
releasenotes/notes/fs-drv-chunk-sz-a1b2f6a72fad92d5.yaml Normal file
View File

@ -0,0 +1,5 @@
---
fixes:
- |
The filesystem driver is now using a configurable chunk size. Increasing it
may avoid bottlenecks.