Re: [PATCH] KVM: selftests: memslot_perf_test: make host wait timeout configurable

[Mayuresh Chitale]

On Tue, Apr 7, 2026 at 4:30 AM Sean Christopherson <seanjc@xxxxxxxxxx> wrote:
>
> On Thu, Apr 02, 2026, Maciej S. Szmigiero wrote:
> > On 2.04.2026 12:29, Mayuresh Chitale wrote:
> > > When memslot_perf_test is run on qemu, sometimes the RW subtest fails
> > > due to sigalarm, indicating that the guest sync did not finish within
> > > the expected duration of 10 seconds. Since the current timeout value is
> > > itself a bump up from the original 2s, making the host timeout value
> > > configurable via a new command line parameter. Now the test can be
> > > invoked with '-a' argument to run the test with a suitable host timeout
> > > value.
> > >
> > > Signed-off-by: Mayuresh Chitale <mayuresh.chitale@xxxxxxxxxxxxxxxx>
> > > ---
> >
> > Out of curiosity: which KVM-enabled setup takes more than 10 seconds
> > to run that RW test?
>
> Hmm, I assume "run on qemu" means running in a VM that's fully emulated by QEMU?
> That would probably explain why it's so slow?

Yes. thats correct. I can update the commit message to reflect that.
>
> > Does it have like, multiple levels of nesting?
> >
> > When I wrote that test I calibrated it on a mid-range x86 machine,
> > where one iteration took on the order of 0.01 s.
> >
> > 10 s time limit per iteration is already three orders of magnitude
> > slower than that.
> >
> > Otherwise, the patch looks sensible to me.
> >
> > Thanks,
> > Maciej
> >