RE: [PATCH v5 0/5] dirty_log_perf_test vCPU pinning

From: Wang, Wei W
Date: Sun Oct 16 2022 - 20:47:44 EST


On Saturday, October 15, 2022 3:03 AM, Sean Christopherson wrote:
> On Fri, Oct 14, 2022, Vipin Sharma wrote:
> > On Fri, Oct 14, 2022 at 9:55 AM David Matlack <dmatlack@xxxxxxxxxx>
> wrote:
> > >
> > > On Fri, Oct 14, 2022 at 9:34 AM Sean Christopherson <seanjc@xxxxxxxxxx>
> wrote:
> > > >
> > > > On Fri, Oct 14, 2022, Wang, Wei W wrote:
> > > > > Just curious why not re-using the existing tools (e.g. taskset) to do the
> pinning?
> > > >
> > > > IIUC, you're suggesting the test give tasks meaningful names so
> > > > that the user can do taskset on the appropriate tasks? The goal
> > > > is to ensure vCPUs are pinned before they do any meaningful work.
> > > > I don't see how that can be accomplished with taskset without some
> > > > form of hook in the test to effectively pause the test until the user (or
> some run script) is ready to continue.
> > >
> > > A taskset approach would also be more difficult to incorporate into
> > > automated runs of dirty_log_perf_test.
> > >
> > > >
> > > > Pinning aside, naming the threads is a great idea! That would
> > > > definitely help debug, e.g. if one vCPU gets stuck or is lagging behind.
> > >
> > > +1
> >
> > I also like the idea.
> >
> > Sean:
> > Do you want a v6 with the naming patch or you will be fine taking v5,
> > if there are no changes needed in v5, and I can send a separate patch
> > for naming?
>
> Definitely separate, this is an orthogonal change and I don't think there will be
> any conflict. If there is a conflict, it will be trivial to resolve. But since Wei
> provided a more or less complete patch, let's let Wei post a formal patch
> (unless he doesn't want to).

Yeah, I'm glad to take care of this. There are other places (e.g. hardware_disable_test.c)
that seem good to have this as well, I'll cover them in one patchset.