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From: Suren Baghdasaryan <surenb@google.com>
Date: Thu, 15 Feb 2024 17:31:41 -0800
Message-ID: <CAJuCfpE9gys=A8A+A9ie92uJXLeYVNyZGGVgxizjEjmRGtjdvg@mail.gmail.com>
Subject: Re: [PATCH v3 31/35] lib: add memory allocations report in show_mem()
To: Kent Overstreet <kent.overstreet@linux.dev>
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On Thu, Feb 15, 2024 at 5:18=E2=80=AFPM Kent Overstreet
<kent.overstreet@linux.dev> wrote:
>
> On Thu, Feb 15, 2024 at 08:12:39PM -0500, Steven Rostedt wrote:
> > On Thu, 15 Feb 2024 19:50:24 -0500
> > Kent Overstreet <kent.overstreet@linux.dev> wrote:
> >
> > > > All nice, but where are the benchmarks? This looks like it will hav=
e an
> > > > affect on cache and you can talk all you want about how it will not=
 be an
> > > > issue, but without real world benchmarks, it's meaningless. Numbers=
 talk.
> > >
> > > Steve, you're being demanding. We provided sufficient benchmarks to s=
how
> > > the overhead is low enough for production, and then I gave you a
> > > detailed breakdown of where our overhead is and where it'll show up. =
I
> > > think that's reasonable.
> >
> > It's not unreasonable or demanding to ask for benchmarks. You showed on=
ly
> > micro-benchmarks that do not show how cache misses may affect the syste=
m.
> > Honestly, it sounds like you did run other benchmarks and didn't like t=
he
> > results and are fighting to not have to produce them. Really, how hard =
is
> > it? There's lots of benchmarks you can run, like hackbench, stress-ng,
> > dbench. Why is this so difficult for you?

I'll run these benchmarks and will include the numbers in the next cover le=
tter.


>
> Woah, this is verging into paranoid conspiracy territory.
>
> No, we haven't done other benchmarks, and if we had we'd be sharing
> them. And if I had more time to spend on performance of this patchset
> that's not where I'd be spending it; the next thing I'd be looking at
> would be assembly output of the hooking code and seeing if I could shave
> that down.
>
> But I already put a ton of work into shaving cycles on this patchset,
> I'm happy with the results, and I have other responsibilities and other
> things I need to be working on.