linux-kernel - Re: [RFC] autonuma: Support to scan page table asynchronously

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <877dyaubsa.fsf@yhuang-dev.intel.com>
Date:   Mon, 20 Apr 2020 10:32:53 +0800
From:   "Huang\, Ying" <ying.huang@...el.com>
To:     SeongJae Park <sj38.park@...il.com>
Cc:     Mel Gorman <mgorman@...e.de>, SeongJae Park <sjpark@...zon.com>,
        Mel Gorman <mgorman@...hsingularity.net>,
        Peter Zijlstra <peterz@...radead.org>, <linux-mm@...ck.org>,
        <linux-kernel@...r.kernel.org>, Ingo Molnar <mingo@...hat.com>,
        Rik van Riel <riel@...riel.com>,
        Daniel Jordan <daniel.m.jordan@...cle.com>,
        Tejun Heo <tj@...nel.org>, Dave Hansen <dave.hansen@...el.com>,
        Tim Chen <tim.c.chen@...el.com>,
        Aubrey Li <aubrey.li@...el.com>
Subject: Re: [RFC] autonuma: Support to scan page table asynchronously

SeongJae Park <sj38.park@...il.com> writes:
>
> DAMON allows users to know which address ranges have which access frequency.
> Thus, I think DAMON could be used for detection of hot pages, which will be
> good migration candidates, instead of the NUMA hinting fault based referenced
> pages detection.
>
> The benefits I expect from this change are better accuracy and less overhead.
> As we can know not only referenced pages but hot pages, migration will be more
> effective.

The purpose of AutoNUMA scanning isn't to find the hot pages, but the
pages that are accessed across NUMA node.  PTE accessed bit cannot
provide information of accessing CPU, so it's not enough for AutoNUMA.

Best Regards,
Huang, Ying