[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <4F0D291A.8030205@lge.com>
Date: Wed, 11 Jan 2012 15:15:54 +0900
From: Namhyung Kim <namhyung.kim@....com>
To: Tejun Heo <tj@...nel.org>
CC: axboe@...nel.dk, mingo@...hat.com, rostedt@...dmis.org,
fweisbec@...il.com, teravest@...gle.com, slavapestov@...gle.com,
ctalbott@...gle.com, dhsharp@...gle.com,
linux-kernel@...r.kernel.org, winget@...gle.com,
Chanho Park <chanho61.park@...sung.com>, namhyung@...il.com
Subject: Re: [PATCH RESEND 9/9] block, trace: implement ioblame - IO tracer
with origin tracking
2012-01-11 10:32 AM, Tejun Heo wrote:
> Implement ioblame, which can attribute each IO to its origin and
> export the information using a tracepoint.
>
> Operations which may eventually cause IOs and IO operations themselves
> are identified and tracked primarily by their stack traces along with
> the task and the target file (dev:ino:gen). On each IO completion,
> ioblame knows why that specific IO happened and exports the
> information via ioblame:ioblame_io tracepoint.
>
> While ioblame adds fields to a few fs and block layer objects, all
> logic is well insulated inside ioblame proper and all hooking goes
> through well defined tracepoints and doesn't add any significant
> maintenance overhead.
>
> For details, please read Documentation/trace/ioblame.txt.
>
> -v2: Namhyung pointed out that all the information available at IO
> completion can be exported via tracepoint and letting userland do
> whatever it wants to do with that would be better. Stripped out
> in-kernel statistics gathering.
>
> Now that everything is exported through tracepoint, iolog and
> counters_pipe[_pipe] are unnecessary. Removed. intents_bin too
> is removed.
>
> As data collection no longer requires polling, ioblame/intents is
> updated to generate inotify IN_MODIFY event after a new intent is
> created.
>
Hi Tejun,
How about adding another tracepoint for intent creation to provide raw
data as well, somewhere in iob_get_intent() or iob_intent_create()
maybe? It can be useful to get those data for further processing IMHO.
Thanks,
Namhyung Kim
--
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/
Powered by blists - more mailing lists