Re: [PATCH 0/5] Add a dirty logging performance test

From: Andrew Jones
Date: Mon Nov 09 2020 - 04:21:33 EST


On Fri, Nov 06, 2020 at 01:48:29PM +0100, Paolo Bonzini wrote:
> On 28/10/20 00:37, Ben Gardon wrote:
> > Currently KVM lacks a simple, userspace agnostic, performance benchmark for
> > dirty logging. Such a benchmark will be beneficial for ensuring that dirty
> > logging performance does not regress, and to give a common baseline for
> > validating performance improvements. The dirty log perf test introduced in
> > this series builds on aspects of the existing demand paging perf test and
> > provides time-based performance metrics for enabling and disabling dirty
> > logging, getting the dirty log, and dirtying memory.
> >
> > While the test currently only has a build target for x86, I expect it will
> > work on, or be easily modified to support other architectures.
> >
> > Ben Gardon (5):
> > KVM: selftests: Factor code out of demand_paging_test
> > KVM: selftests: Remove address rounding in guest code
> > KVM: selftests: Simplify demand_paging_test with timespec_diff_now
> > KVM: selftests: Add wrfract to common guest code
> > KVM: selftests: Introduce the dirty log perf test
> >
> > tools/testing/selftests/kvm/.gitignore | 1 +
> > tools/testing/selftests/kvm/Makefile | 1 +
> > .../selftests/kvm/demand_paging_test.c | 230 ++---------
> > .../selftests/kvm/dirty_log_perf_test.c | 382 ++++++++++++++++++
> > .../selftests/kvm/include/perf_test_util.h | 192 +++++++++
> > .../testing/selftests/kvm/include/test_util.h | 2 +
> > tools/testing/selftests/kvm/lib/test_util.c | 22 +-
> > 7 files changed, 635 insertions(+), 195 deletions(-)
> > create mode 100644 tools/testing/selftests/kvm/dirty_log_perf_test.c
> > create mode 100644 tools/testing/selftests/kvm/include/perf_test_util.h
> >
>
> Queued, thanks.

Why would you do that? Peter reviewed this, making several comments,
such as not to put non-inline functions in header files. Ben took the
time to respin the series, posting a v2. It makes no sense to pick up
v1 after they put in that additional effort.

drew