Commit Graph

7 Commits

Author SHA1 Message Date
Ben Gardon
4fd94ec7d5 KVM: selftests: Introduce the dirty log perf test
The dirty log perf test will time verious dirty logging operations
(enabling dirty logging, dirtying memory, getting the dirty log,
clearing the dirty log, and disabling dirty logging) in order to
quantify dirty logging performance. This test can be used to inform
future performance improvements to KVM's dirty logging infrastructure.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201027233733.1484855-6-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-08 06:04:08 -05:00
Andrew Jones
3be1863095 KVM: selftests: Make the number of vcpus global
We also check the input number of vcpus against the maximum supported.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Message-Id: <20201104212357.171559-8-drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-08 06:04:03 -05:00
Andrew Jones
6769155fec KVM: selftests: Make the per vcpu memory size global
Rename vcpu_memory_bytes to something with "percpu" in it
in order to be less ambiguous. Also make it global to
simplify things.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Message-Id: <20201104212357.171559-7-drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-08 06:03:55 -05:00
Andrew Jones
f663132d1e KVM: selftests: Drop pointless vm_create wrapper
Signed-off-by: Andrew Jones <drjones@redhat.com>
Message-Id: <20201104212357.171559-3-drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-08 06:03:36 -05:00
Ben Gardon
92ab4b9a22 KVM: selftests: Add wrfract to common guest code
Wrfract will be used by the dirty logging perf test introduced later in
this series to dirty memory sparsely.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201027233733.1484855-5-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-08 06:03:35 -05:00
Ben Gardon
2fe5149bdf KVM: selftests: Remove address rounding in guest code
Rounding the address the guest writes to a host page boundary
will only have an effect if the host page size is larger than the guest
page size, but in that case the guest write would still go to the same
host page. There's no reason to round the address down, so remove the
rounding to simplify the demand paging test.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201027233733.1484855-3-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-08 06:03:34 -05:00
Ben Gardon
4b5d12b0e2 KVM: selftests: Factor code out of demand_paging_test
Much of the code in demand_paging_test can be reused by other, similar
multi-vCPU-memory-touching-perfromance-tests. Factor that common code
out for reuse.

No functional change expected.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201027233733.1484855-2-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-08 06:03:34 -05:00