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

[Sean Christopherson <seanjc@google.com>]

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@oss.qualcomm.com>
> > ---
> 
> 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?

> 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
>