linux-kernel - Re: [PATCH 1/3] mm/compaction: enhance trace output to know more about compaction internals

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: <20150109105710.GN2395@suse.de>
Date:	Fri, 9 Jan 2015 10:57:10 +0000
From:	Mel Gorman <mgorman@...e.de>
To:	Vlastimil Babka <vbabka@...e.cz>
Cc:	Joonsoo Kim <iamjoonsoo.kim@....com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	David Rientjes <rientjes@...gle.com>, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/3] mm/compaction: enhance trace output to know more
 about compaction internals

On Thu, Jan 08, 2015 at 09:46:27AM +0100, Vlastimil Babka wrote:
> On 01/08/2015 09:18 AM, Joonsoo Kim wrote:
> > On Tue, Jan 06, 2015 at 10:05:39AM +0100, Vlastimil Babka wrote:
> >> On 12/03/2014 08:52 AM, Joonsoo Kim wrote:
> >> > It'd be useful to know where the both scanner is start. And, it also be
> >> > useful to know current range where compaction work. It will help to find
> >> > odd behaviour or problem on compaction.
> >> 
> >> Overall it looks good, just two questions:
> >> 1) Why change the pfn output to hexadecimal with different printf layout and
> >> change the variable names and? Is it that better to warrant people having to
> >> potentially modify their scripts parsing the old output?
> > 
> > Deciaml output has really bad readability since we manage all pages by order
> > of 2 which is well represented by hexadecimal. With hex output, we can
> > easily notice whether we move out from one pageblock to another one.
> 
> OK. I don't have any strong objection, maybe Mel should comment on this as the
> author of most of the tracepoints? But if it happens, I think converting the old
> tracepoints to new hexadecimal format should be a separate patch from adding the
> new ones.
> 

To date, I'm not aware of any user-space programs that heavily depend on
the formatting. The scripts I am aware of are ad-hoc and easily modified
to adapt to format changes. LTT-NG is the only tool that might be
depending on trace point formats but I severely doubt it's interested in
this particular tracepoint.

-- 
Mel Gorman
SUSE Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/