public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
To: Valdis.Kletnieks@vt.edu
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>,
	Ingo Molnar <mingo@elte.hu>,
	Dhaval Giani <dhaval@linux.vnet.ibm.com>,
	Mike Galbraith <efault@gmx.de>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Dmitry Adamushko <dmitry.adamushko@gmail.com>,
	lkml <linux-kernel@vger.kernel.org>,
	maneesh@linux.vnet.ibm.com,
	Andrew Morton <akpm@linux-foundation.org>,
	Sudhir Kumar <skumar@linux.vnet.ibm.com>
Subject: Re: [RFC/PATCH -v2] Add sysfs control to modify a user's cpu share
Date: Fri, 5 Oct 2007 12:31:17 +0530	[thread overview]
Message-ID: <20071005070117.GB30528@linux.vnet.ibm.com> (raw)
In-Reply-To: <5596.1191533537@turing-police.cc.vt.edu>

On Thu, Oct 04, 2007 at 05:32:17PM -0400, Valdis.Kletnieks@vt.edu wrote:
> > Shouldn't that be done via uevents? E.g. UID x gets added to the sysfs tree,
> > generates a uevent and a script then figures out the cpu_share and sets it.
> 
> That would tend to be a tad racy - a site may want to set limits in the
> hypothetical /sys/kernel/uids/NNN before the program has a chance to fork-bomb
> or otherwise make it difficult to set a limitfrom within another userspace

Note that there is a default limit enforced on every new user (1024
value for the user's cpu share). This limit should contain any fork-bomb that
the user may launch immediately.

> process.  It's similar to why you want a process to be launched with all its
> ulimit's set, rather than set them after the fork/exec happens...





-- 
Regards,
vatsa

  reply	other threads:[~2007-10-05  6:50 UTC|newest]

Thread overview: 53+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-09-24 21:45 [git] CFS-devel, latest code Ingo Molnar
2007-09-24 21:55 ` Andrew Morton
2007-09-24 21:59   ` Ingo Molnar
2007-09-25  0:08 ` Daniel Walker
2007-09-25  6:45   ` Ingo Molnar
2007-09-25 15:17     ` Daniel Walker
2007-09-25  6:10 ` Mike Galbraith
2007-09-25  7:35   ` Mike Galbraith
2007-09-25  8:33     ` Mike Galbraith
2007-09-25  8:53       ` Srivatsa Vaddagiri
2007-09-25  9:11         ` Srivatsa Vaddagiri
2007-09-25  9:15           ` Mike Galbraith
2007-09-25  9:12         ` Mike Galbraith
2007-09-25  9:13       ` Ingo Molnar
2007-09-25  9:17         ` Mike Galbraith
2007-09-25  9:47           ` Ingo Molnar
2007-09-25 10:02             ` Mike Galbraith
2007-09-26  8:04             ` Mike Galbraith
2007-09-28 21:46             ` Bill Davidsen
2007-09-25  9:44         ` Srivatsa Vaddagiri
2007-09-25  9:40           ` Ingo Molnar
2007-09-25 10:10             ` Ingo Molnar
2007-09-25 10:28               ` Srivatsa Vaddagiri
2007-09-25 10:36                 ` Ingo Molnar
2007-09-25 11:33                   ` Ingo Molnar
2007-09-25 14:48                     ` Srivatsa Vaddagiri
2007-09-25 12:51                   ` Srivatsa Vaddagiri
2007-09-25 13:35                     ` Mike Galbraith
2007-09-25 14:07                       ` Srivatsa Vaddagiri
2007-09-25 12:28                 ` Mike Galbraith
2007-09-25 12:54                   ` Mike Galbraith
     [not found]                     ` <20070925131717.GM26289@linux.vnet.ibm.com>
     [not found]                       ` <1190725693.13716.10.camel@Homer.simpson.net>
     [not found]                         ` <20070925132528.GN26289@linux.vnet.ibm.com>
     [not found]                           ` <1190726682.11260.1.camel@Homer.simpson.net>
     [not found]                             ` <20070925140559.GB26310@linux.vnet.ibm.com>
     [not found]                               ` <20070925143755.GA15594@elte.hu>
     [not found]                                 ` <20070926210737.GA8663@elte.hu>
2007-10-01 14:04                                   ` [RFC/PATCH] Add sysfs control to modify a user's cpu share Dhaval Giani
2007-10-01 14:44                                     ` Ingo Molnar
2007-10-01 15:32                                       ` Srivatsa Vaddagiri
2007-10-02 22:12                                       ` Eric St-Laurent
2007-10-03  4:09                                         ` Srivatsa Vaddagiri
2007-10-03 17:10                                       ` [RFC/PATCH -v2] " Dhaval Giani
2007-10-04  7:57                                         ` Ingo Molnar
2007-10-04  8:54                                           ` Heiko Carstens
2007-10-04 16:02                                             ` Bill Davidsen
2007-10-04 17:20                                               ` Srivatsa Vaddagiri
2007-10-04 21:32                                             ` Valdis.Kletnieks
2007-10-05  7:01                                               ` Srivatsa Vaddagiri [this message]
2007-10-09 15:12                                             ` [PATCH sched-devel] Generate uevents for user creation/destruction Srivatsa Vaddagiri
2007-10-10  7:42                                               ` Ingo Molnar
2007-10-01 16:12                                     ` [RFC/PATCH] Add sysfs control to modify a user's cpu share Dave Jones
2007-10-01 16:37                                       ` Srivatsa Vaddagiri
2007-09-25  6:50 ` [git] CFS-devel, latest code S.Çağlar Onur
2007-09-25  9:17   ` Ingo Molnar
2007-09-25  7:41 ` Andrew Morton
2007-09-25  8:43   ` Srivatsa Vaddagiri
2007-09-25  8:48     ` Andrew Morton
2007-09-25 11:00     ` Ingo Molnar

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20071005070117.GB30528@linux.vnet.ibm.com \
    --to=vatsa@linux.vnet.ibm.com \
    --cc=Valdis.Kletnieks@vt.edu \
    --cc=a.p.zijlstra@chello.nl \
    --cc=akpm@linux-foundation.org \
    --cc=dhaval@linux.vnet.ibm.com \
    --cc=dmitry.adamushko@gmail.com \
    --cc=efault@gmx.de \
    --cc=heiko.carstens@de.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=maneesh@linux.vnet.ibm.com \
    --cc=mingo@elte.hu \
    --cc=skumar@linux.vnet.ibm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox