openstack
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nova
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Merge "Optimize numa_fit_instance_to_host"

This commit is contained in:
Zuul 2022-08-11 01:52:59 +00:00 committed by Gerrit Code Review
parent e90fcc1535 099a6f63af
commit f77c58dd98
3 changed files with 125 additions and 27 deletions
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111
nova/tests/unit/virt/test_hardware.py
View File

@ -3836,9 +3836,16 @@ class CPUPinningTestCase(test.NoDBTestCase, _CPUPinningTestCaseBase):
siblings=[set([2]), set([3])])
])
inst_topo = objects.InstanceNUMATopology(
cells=[objects.InstanceNUMACell(
cpuset=set(), pcpuset=set([0, 1]), memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED)])
cells=[
objects.InstanceNUMACell(
id=0,
cpuset=set(),
pcpuset=set([0, 1]),
memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED,
)
]
)
inst_topo = hw.numa_fit_instance_to_host(host_topo, inst_topo)
@ -3867,9 +3874,16 @@ class CPUPinningTestCase(test.NoDBTestCase, _CPUPinningTestCaseBase):
siblings=[set([2]), set([3])])
])
inst_topo = objects.InstanceNUMATopology(
cells=[objects.InstanceNUMACell(
cpuset=set(), pcpuset=set([0, 1]), memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED)])
cells=[
objects.InstanceNUMACell(
id=0,
cpuset=set(),
pcpuset=set([0, 1]),
memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED,
)
]
)
inst_topo = hw.numa_fit_instance_to_host(host_topo, inst_topo)
@ -3898,9 +3912,16 @@ class CPUPinningTestCase(test.NoDBTestCase, _CPUPinningTestCaseBase):
siblings=[set([2]), set([3])])
])
inst_topo = objects.InstanceNUMATopology(
cells=[objects.InstanceNUMACell(
cpuset=set(), pcpuset=set([0, 1]), memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED)])
cells=[
objects.InstanceNUMACell(
id=0,
cpuset=set(),
pcpuset=set([0, 1]),
memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED,
)
]
)
inst_topo = hw.numa_fit_instance_to_host(host_topo, inst_topo)
self.assertIsNone(inst_topo)
@ -3927,12 +3948,24 @@ class CPUPinningTestCase(test.NoDBTestCase, _CPUPinningTestCaseBase):
siblings=[set([4]), set([5]), set([6]), set([7])])
])
inst_topo = objects.InstanceNUMATopology(
cells=[objects.InstanceNUMACell(
cpuset=set(), pcpuset=set([0, 1]), memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED),
objects.InstanceNUMACell(
cpuset=set(), pcpuset=set([2, 3]), memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED)])
cells=[
objects.InstanceNUMACell(
id=0,
cpuset=set(),
pcpuset=set([0, 1]),
memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED,
),
objects.InstanceNUMACell(
id=1,
cpuset=set(),
pcpuset=set([2, 3]),
memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED,
),
]
)
inst_topo = hw.numa_fit_instance_to_host(host_topo, inst_topo)
for cell in inst_topo.cells:
@ -3970,12 +4003,24 @@ class CPUPinningTestCase(test.NoDBTestCase, _CPUPinningTestCaseBase):
])
inst_topo = objects.InstanceNUMATopology(
cells=[objects.InstanceNUMACell(
cpuset=set(), pcpuset=set([0, 1]), memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED),
objects.InstanceNUMACell(
cpuset=set(), pcpuset=set([2, 3]), memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED)])
cells=[
objects.InstanceNUMACell(
id=0,
cpuset=set(),
pcpuset=set([0, 1]),
memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED,
),
objects.InstanceNUMACell(
id=1,
cpuset=set(),
pcpuset=set([2, 3]),
memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED,
),
]
)
inst_topo = hw.numa_fit_instance_to_host(host_topo, inst_topo)
for cell in inst_topo.cells:
@ -4003,12 +4048,24 @@ class CPUPinningTestCase(test.NoDBTestCase, _CPUPinningTestCaseBase):
siblings=[set([4]), set([5]), set([6]), set([7])])
])
inst_topo = objects.InstanceNUMATopology(
cells=[objects.InstanceNUMACell(
cpuset=set(), pcpuset=set([0, 1]), memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED),
objects.InstanceNUMACell(
cpuset=set(), pcpuset=set([2, 3]), memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED)])
cells=[
objects.InstanceNUMACell(
id=0,
cpuset=set(),
pcpuset=set([0, 1]),
memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED,
),
objects.InstanceNUMACell(
id=1,
cpuset=set(),
pcpuset=set([2, 3]),
memory=2048,
cpu_policy=fields.CPUAllocationPolicy.DEDICATED,
),
]
)
inst_topo = hw.numa_fit_instance_to_host(host_topo, inst_topo)
self.assertIsNone(inst_topo)

32
nova/virt/hardware.py
View File

@ -2357,12 +2357,37 @@ def numa_fit_instance_to_host(
host_cells,
key=lambda cell: total_pci_in_cell.get(cell.id, 0))
# a set of host_cell.id, instance_cell.id pairs where we already checked
# that the instance cell does not fit
not_fit_cache = set()
# a set of host_cell.id, instance_cell.id pairs where we already checked
# that the instance cell does fit
fit_cache = set()
for host_cell_perm in itertools.permutations(
host_cells, len(instance_topology)):
chosen_instance_cells: ty.List['objects.InstanceNUMACell'] = []
chosen_host_cells: ty.List['objects.NUMACell'] = []
for host_cell, instance_cell in zip(
host_cell_perm, instance_topology.cells):
cell_pair = (host_cell.id, instance_cell.id)
# if we already checked this pair, and they did not fit then no
# need to check again just move to the next permutation
if cell_pair in not_fit_cache:
break
# if we already checked this pair, and they fit before that they
# will fit now too. So no need to check again. Just continue with
# the next cell pair in the permutation
if cell_pair in fit_cache:
chosen_host_cells.append(host_cell)
# Normally this would have done by _numa_fit_instance_cell
# but we optimized that out here based on the cache
instance_cell.id = host_cell.id
chosen_instance_cells.append(instance_cell)
continue
try:
cpuset_reserved = 0
if (instance_topology.emulator_threads_isolated and
@ -2379,11 +2404,18 @@ def numa_fit_instance_to_host(
# This exception will been raised if instance cell's
# custom pagesize is not supported with host cell in
# _numa_cell_supports_pagesize_request function.
# cache the result
not_fit_cache.add(cell_pair)
break
if got_cell is None:
# cache the result
not_fit_cache.add(cell_pair)
break
chosen_host_cells.append(host_cell)
chosen_instance_cells.append(got_cell)
# cache the result
fit_cache.add(cell_pair)
if len(chosen_instance_cells) != len(host_cell_perm):
continue

9
releasenotes/notes/bug-1978372-optimized-numa-fitting-algorithm-5d5b922b0bdbf818.yaml Normal file
View File

@ -0,0 +1,9 @@
---
fixes:
- |
The algorithm that is used to see if a multi NUMA guest fits to
a multi NUMA host has been optimized to speed up the decision
on hosts with high number of NUMA nodes ( > 8). For details see
`bug 1978372`_
.. _bug 1978372: https://bugs.launchpad.net/nova/+bug/1978372