From: Marcelo Tosatti <mtosatti@redhat.com>
To: Pekka Enberg <penberg@kernel.org>
Cc: leonid.moiseichuk@nokia.com, rhod@redhat.com, riel@redhat.com,
minchan@kernel.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org, kamezawa.hiroyu@jp.fujitsu.com,
mel@csn.ul.ie, rientjes@google.com, kosaki.motohiro@gmail.com,
hannes@cmpxchg.org, akpm@linux-foundation.org,
kosaki.motohiro@jp.fujitsu.com
Subject: Re: [RFC 1/3] /dev/low_mem_notify
Date: Tue, 24 Jan 2012 16:29:09 -0200 [thread overview]
Message-ID: <20120124182909.GB19186@amt.cnet> (raw)
In-Reply-To: <1327421440.13624.30.camel@jaguar>
On Tue, Jan 24, 2012 at 06:10:40PM +0200, Pekka Enberg wrote:
> On Tue, 2012-01-24 at 13:38 -0200, Marcelo Tosatti wrote:
> > Having userspace specify the "sample period" for low memory notification
> > makes no sense. The frequency of notifications is a function of the
> > memory pressure.
>
> Sure, it makes sense to autotune sample period. I don't see the problem
> with letting userspace decide it for themselves if they want to.
>
> Pekka
Application polls on a file descriptor waiting for asynchronous events,
particular conditions of memory reclaim upon which an action is
necessary.
These signalled conditions are not simply percentages of free memory,
but depend on the amount of freeable cache available, etc. Otherwise
applications could monitor /proc/mem_info and act on that.
What is the point of sampling in the interface as you have it?
Application can read() from the file descriptor to retrieve the current
status, if it wishes.
The objective in this argument is to make the API as simple and easy to
use as possible.
next prev parent reply other threads:[~2012-01-24 18:31 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-17 8:13 [RFC 0/3] low memory notify Minchan Kim
2012-01-17 8:13 ` [RFC 1/3] /dev/low_mem_notify Minchan Kim
2012-01-17 9:27 ` Pekka Enberg
2012-01-17 16:35 ` Rik van Riel
2012-01-17 18:51 ` Pekka Enberg
2012-01-17 19:30 ` Rik van Riel
2012-01-17 19:49 ` Pekka Enberg
2012-01-17 19:54 ` Pekka Enberg
2012-01-17 19:57 ` Pekka Enberg
2012-01-17 23:20 ` Minchan Kim
2012-01-18 7:16 ` Pekka Enberg
2012-01-18 7:49 ` Minchan Kim
2012-01-18 9:06 ` leonid.moiseichuk
2012-01-18 9:15 ` Pekka Enberg
2012-01-18 9:41 ` leonid.moiseichuk
2012-01-18 10:40 ` Pekka Enberg
2012-01-18 10:44 ` leonid.moiseichuk
2012-01-18 23:34 ` Ronen Hod
2012-01-19 7:25 ` Pekka Enberg
2012-01-19 9:05 ` Ronen Hod
2012-01-19 9:10 ` Pekka Enberg
2012-01-19 9:20 ` Ronen Hod
2012-01-19 10:53 ` leonid.moiseichuk
2012-01-19 11:07 ` Pekka Enberg
2012-01-19 11:54 ` leonid.moiseichuk
2012-01-19 11:59 ` Pekka Enberg
2012-01-19 12:06 ` Pekka Enberg
2012-01-24 15:38 ` Marcelo Tosatti
2012-01-24 16:08 ` Ronen Hod
2012-01-24 18:10 ` Marcelo Tosatti
2012-01-25 8:52 ` Ronen Hod
2012-01-25 10:12 ` Marcelo Tosatti
2012-01-25 10:48 ` Ronen Hod
2012-01-26 16:17 ` Marcelo Tosatti
2012-01-24 16:10 ` Pekka Enberg
2012-01-24 18:29 ` Marcelo Tosatti [this message]
2012-01-25 8:19 ` leonid.moiseichuk
2012-01-19 7:34 ` Pekka Enberg
2012-01-24 16:22 ` Arnd Bergmann
2012-01-18 14:30 ` Rik van Riel
2012-01-18 15:29 ` Pekka Enberg
2012-01-24 15:40 ` Marcelo Tosatti
2012-01-24 16:01 ` Pekka Enberg
2012-01-24 16:25 ` Arnd Bergmann
2012-01-24 18:32 ` Marcelo Tosatti
2012-01-24 21:57 ` Jonathan Corbet
2012-01-17 9:45 ` Pekka Enberg
2012-01-17 8:13 ` [RFC 2/3] vmscan hook Minchan Kim
2012-01-17 8:39 ` KAMEZAWA Hiroyuki
2012-01-17 9:13 ` Minchan Kim
2012-01-17 10:05 ` KAMEZAWA Hiroyuki
2012-01-17 23:08 ` Minchan Kim
2012-01-18 0:18 ` KAMEZAWA Hiroyuki
2012-01-18 14:17 ` Rik van Riel
2012-01-19 2:25 ` KAMEZAWA Hiroyuki
2012-01-19 14:42 ` Rik van Riel
2012-01-20 0:24 ` KAMEZAWA Hiroyuki
2012-01-17 8:13 ` [RFC 3/3] test program Minchan Kim
2012-01-17 14:38 ` [RFC 0/3] low memory notify Colin Walters
2012-01-17 15:04 ` Pekka Enberg
2012-01-17 16:44 ` Rik van Riel
2012-01-17 17:16 ` Olof Johansson
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