mirror of
https://github.com/retspen/webvirtcloud
synced 2026-11-08 19:26:48 +00:00
57f592df70
The overview read the host's info four times, now once (12 libvirt calls). A connection object keeps it next to the capabilities, and the VM page and VM stats take it from there; the VM page's cached_reads block holds only the VM's own data. Free memory is still read each time.
207 lines
7.1 KiB
Python
207 lines
7.1 KiB
Python
"""wvmInstance.cached_reads(): inside the block the domain XML (per flags),
|
|
the VM's state and each disk's volume are read from libvirt once; outside it
|
|
every read goes to libvirt, as code that changes the VM needs. The host's
|
|
info and capabilities are read once per object."""
|
|
|
|
import unittest
|
|
from unittest.mock import MagicMock
|
|
|
|
from django.conf import settings
|
|
|
|
if not settings.configured:
|
|
settings.configure(MAC_OUI="52:54:10")
|
|
|
|
from libvirt import libvirtError
|
|
from vrtManager.instance import wvmInstance
|
|
|
|
|
|
class FakeDomain:
|
|
def __init__(self):
|
|
self.reads = []
|
|
self.fail = False
|
|
|
|
def info(self):
|
|
self.reads.append("info")
|
|
return [1, 0, 0, 0, 0]
|
|
|
|
def XMLDesc(self, flags):
|
|
if self.fail:
|
|
raise RuntimeError("libvirt error")
|
|
self.reads.append(flags)
|
|
return f"<domain flags='{flags}' read='{len(self.reads)}'/>"
|
|
|
|
|
|
class FakeConn:
|
|
def __init__(self):
|
|
self.caps = 0
|
|
self.defined = []
|
|
|
|
def getInfo(self):
|
|
self.caps += 1
|
|
return ["x86_64", 2048, 4, 0, 1, 2, 2, 1]
|
|
|
|
def getCapabilities(self):
|
|
self.caps += 1
|
|
return "<capabilities/>"
|
|
|
|
def defineXML(self, xml):
|
|
self.defined.append(xml)
|
|
|
|
|
|
def proxy():
|
|
p = wvmInstance.__new__(wvmInstance) # no connection: only these calls
|
|
p.instance = FakeDomain()
|
|
p.wvm = FakeConn()
|
|
return p
|
|
|
|
|
|
class CachedReadsTestCase(unittest.TestCase):
|
|
def test_outside_the_block_every_read_goes_to_libvirt(self):
|
|
p = proxy()
|
|
p._XMLDesc(0)
|
|
p._XMLDesc(0)
|
|
p.get_status()
|
|
p.get_status()
|
|
self.assertEqual(p.instance.reads, [0, 0, "info", "info"])
|
|
|
|
def test_inside_the_block_each_flags_value_is_read_once(self):
|
|
p = proxy()
|
|
with p.cached_reads():
|
|
first = [p._XMLDesc(0), p._XMLDesc(1), p._XMLDesc(3)]
|
|
again = [p._XMLDesc(0), p._XMLDesc(1), p._XMLDesc(3)]
|
|
self.assertEqual(first, again)
|
|
self.assertEqual(p.instance.reads, [0, 1, 3])
|
|
|
|
def test_the_block_ends_with_its_cache(self):
|
|
p = proxy()
|
|
with p.cached_reads():
|
|
p._XMLDesc(0)
|
|
with p.cached_reads():
|
|
p._XMLDesc(0)
|
|
p._XMLDesc(0)
|
|
self.assertEqual(p.instance.reads, [0, 0, 0])
|
|
|
|
def test_an_error_inside_the_block_still_ends_it(self):
|
|
p = proxy()
|
|
with self.assertRaises(ValueError), p.cached_reads():
|
|
p._XMLDesc(0)
|
|
raise ValueError
|
|
p._XMLDesc(0)
|
|
self.assertEqual(p.instance.reads, [0, 0])
|
|
|
|
def test_a_failed_read_is_not_cached(self):
|
|
p = proxy()
|
|
with p.cached_reads():
|
|
p.instance.fail = True
|
|
with self.assertRaises(RuntimeError):
|
|
p._XMLDesc(0)
|
|
p.instance.fail = False
|
|
p._XMLDesc(0)
|
|
self.assertEqual(p.instance.reads, [0])
|
|
|
|
def test_a_definition_change_drops_the_cache(self):
|
|
p = proxy()
|
|
with p.cached_reads():
|
|
p._XMLDesc(3)
|
|
p._defineXML("<domain/>")
|
|
p._XMLDesc(3)
|
|
self.assertEqual(p.instance.reads, [3, 3])
|
|
|
|
def test_blocks_do_not_nest(self):
|
|
p = proxy()
|
|
with p.cached_reads(), self.assertRaises(RuntimeError), p.cached_reads():
|
|
pass
|
|
|
|
def test_two_proxies_do_not_share_a_cache(self):
|
|
a, b = proxy(), proxy()
|
|
with a.cached_reads():
|
|
a._XMLDesc(0)
|
|
b._XMLDesc(0)
|
|
b._XMLDesc(0)
|
|
self.assertEqual((a.instance.reads, b.instance.reads), ([0], [0, 0]))
|
|
|
|
def test_the_state_and_host_info_are_read_once(self):
|
|
p = proxy()
|
|
with p.cached_reads():
|
|
for _ in range(2):
|
|
p.get_status()
|
|
p.get_max_memory()
|
|
p.get_max_cpus()
|
|
self.assertEqual((p.instance.reads, p.wvm.caps), (["info"], 1))
|
|
p.get_status()
|
|
self.assertEqual(p.instance.reads, ["info", "info"])
|
|
|
|
def volume_proxy(paths):
|
|
"""A proxy whose host has volumes at paths (pool "pool", size 10, used 4)."""
|
|
p = proxy()
|
|
p.lookups = []
|
|
|
|
def lookup(path):
|
|
p.lookups.append(path)
|
|
if path not in paths:
|
|
raise libvirtError("no storage vol with matching path")
|
|
vol = MagicMock()
|
|
vol.name.return_value = path.rsplit("/", 1)[-1]
|
|
vol.info.return_value = [0, 10, 4]
|
|
vol.storagePoolLookupByVolume.return_value.name.return_value = "pool"
|
|
return vol
|
|
|
|
p.get_volume_by_path = lookup
|
|
return p
|
|
|
|
|
|
class VolumeDetailsTestCase(unittest.TestCase):
|
|
def test_inside_the_block_each_path_is_looked_up_once(self):
|
|
p = volume_proxy({"/p/a.qcow2", "/p/b.raw"})
|
|
with p.cached_reads():
|
|
for _ in range(2):
|
|
self.assertEqual(p._volume_details("/p/a.qcow2"), ("a.qcow2", 10, 4, "pool"))
|
|
p._volume_details("/p/b.raw")
|
|
self.assertIsNone(p._volume_details("/dev/sdx"))
|
|
self.assertEqual(p.lookups, ["/p/a.qcow2", "/p/b.raw", "/dev/sdx"])
|
|
|
|
def test_outside_the_block_and_after_a_change_the_volume_is_read_again(self):
|
|
p = volume_proxy({"/p/a.qcow2"})
|
|
p._volume_details("/p/a.qcow2")
|
|
with p.cached_reads():
|
|
p._volume_details("/p/a.qcow2")
|
|
p._defineXML("<domain/>")
|
|
p._volume_details("/p/a.qcow2")
|
|
p._volume_details("/p/a.qcow2")
|
|
self.assertEqual(len(p.lookups), 4)
|
|
|
|
|
|
def disk(path, cache):
|
|
return (
|
|
f"<disk type='file' device='disk'><driver name='qemu' type='qcow2' cache='{cache}'/>"
|
|
f"<source file='{path}'/><target dev='vda' bus='virtio'/></disk>"
|
|
)
|
|
|
|
|
|
class DiskListsTestCase(unittest.TestCase):
|
|
"""The page lists the running and the persistent disks; both share a
|
|
path's volume, each keeps its own settings."""
|
|
|
|
def lists(self, live, config, volumes):
|
|
p = volume_proxy(volumes)
|
|
xml = {0: f"<domain><devices>{live}</devices></domain>", 3: f"<domain><devices>{config}</devices></domain>"}
|
|
p.instance.XMLDesc = lambda flags: xml[flags]
|
|
with p.cached_reads():
|
|
return p, p.get_disk_devices(), p.get_disk_devices(config=True)
|
|
|
|
def test_one_path_in_both_lists_is_looked_up_once(self):
|
|
p, live, config = self.lists(disk("/p/a.qcow2", "none"), disk("/p/a.qcow2", "writeback"), {"/p/a.qcow2"})
|
|
self.assertEqual(p.lookups, ["/p/a.qcow2"])
|
|
self.assertEqual([(d["image"], d["storage"], d["size"], d["cache"]) for d in live], [("a.qcow2", "pool", 10, "none")])
|
|
self.assertEqual([d["cache"] for d in config], ["writeback"])
|
|
self.assertIsNot(live[0], config[0])
|
|
|
|
def test_a_pending_disk_change_is_looked_up_on_its_own(self):
|
|
p, live, config = self.lists(disk("/p/a.qcow2", "none"), disk("/p/b.qcow2", "none"), {"/p/a.qcow2", "/p/b.qcow2"})
|
|
self.assertEqual(p.lookups, ["/p/a.qcow2", "/p/b.qcow2"])
|
|
self.assertEqual((live[0]["image"], config[0]["image"]), ("a.qcow2", "b.qcow2"))
|
|
|
|
def test_a_disk_outside_any_pool_shows_its_path(self):
|
|
p, live, _ = self.lists(disk("/srv/x.img", "none"), disk("/srv/x.img", "none"), set())
|
|
self.assertEqual(p.lookups, ["/srv/x.img"])
|
|
self.assertEqual((live[0]["image"], live[0]["storage"], live[0]["size"]), ("/srv/x.img", None, None))
|