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Date:   Wed, 29 Jan 2020 19:07:09 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     sjpark@amazon.com
Cc:     akpm@linux-foundation.org, SeongJae Park <sjpark@amazon.de>,
        sj38.park@gmail.com, acme@kernel.org, amit@kernel.org,
        brendan.d.gregg@gmail.com, corbet@lwn.net, dwmw@amazon.com,
        mgorman@suse.de, rostedt@goodmis.org, kirill@shutemov.name,
        brendanhiggins@google.com, colin.king@canonical.com,
        minchan@kernel.org, vdavydov.dev@gmail.com, vdavydov@parallels.com,
        linux-mm@kvack.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@redhat.com>,
        Namhyung Kim <namhyung@kernel.org>
Subject: Re: Re: Re: [PATCH v2 0/9] Introduce Data Access MONitor (DAMON)
Message-ID: <20200129180709.GS14879@hirez.programming.kicks-ass.net>
References: <20200129125615.GQ14879@hirez.programming.kicks-ass.net>
 <20200129143758.896-1-sjpark@amazon.com>
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On Wed, Jan 29, 2020 at 03:37:58PM +0100, sjpark@amazon.com wrote:
> On Wed, 29 Jan 2020 13:56:15 +0100 Peter Zijlstra <peterz@infradead.org> wrote:
> 
> > On Tue, Jan 28, 2020 at 01:00:33PM +0100, sjpark@amazon.com wrote:
> > 
> > > I worried whether it could be a bother to send the mail to everyone in the
> > > section, but seems it was an unnecessary worry.  Adding those to recipients.
> > > You can get the original thread of this patchset from
> > > https://lore.kernel.org/linux-mm/20200128085742.14566-1-sjpark@amazon.com/
> > 
> > I read first patch (the document) and still have no friggin clue.
> 
> Do you mean the document has insufficient description only?  If so, could you
> please point me me which information do you want to be added?

There was a lot of words; but I'm still not sure what it actually does.

I've read some of the code that followed; is it simply sampling the
page-table access bit? It did some really weird things though, like that
whole 3 regions thing.

Also, you wrote you wanted feedback from perf people; but it doesn't use
perf, what are you asking?

Perf can do address based sampling of memops, I suspect you can create
something using that.