lkml.org 
[lkml]   [2016]   [Jul]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 00/14] Present useful limits to user (v2)
From
Date
<lizefan@huawei.com>,Johannes Weiner <hannes@cmpxchg.org>,Alexei Starovoitov <ast@kernel.org>,Arnaldo Carvalho de Melo <acme@kernel.org>,Alexander Shishkin <alexander.shishkin@linux.intel.com>,Balbir Singh <bsingharora@gmail.com>,Markus Elfring <elfring@users.sourceforge.net>,"David S. Miller" <davem@davemloft.net>,Nicolas Dichtel <nicolas.dichtel@6wind.com>,Andrew Morton <akpm@linux-foundation.org>,Konstantin Khlebnikov <koct9i@gmail.com>,Jiri Slaby <jslaby@suse.cz>,Cyrill Gorcunov <gorcunov@openvz.org>,Michal Hocko <mhocko@suse.com>,Vlastimil Babka <vbabka@suse.cz>,Dave Hansen <dave.hansen@linux.intel.com>,Greg Kroah-Hartman <gregkh@linuxfoundation.org>,Dan Carpenter <dan.carpenter@oracle.com>,Michael Kerrisk <mtk.manpages@gmail.com>,"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,Marcus Gelderie <redmnic@gmail.com>,Vladimir Davydov <vdavydov@virtuozzo.com>,Joe Perches <joe@perches.com>,Frederic Weisbecker <fweisbec@gmail.com>,Andrea Arcangeli <aarcange@redhat.com>,!
"Eric W.
Biederman" <ebiederm@xmission.com>,Andi Kleen <ak@linux.intel.com>,Oleg Nesterov <oleg@redhat.com>,Stas Sergeev <stsp@list.ru>,Amanieu d'Antras <amanieu@gmail.com>,Richard Weinberger <richard@nod.at>,Wang Xiaoqiang <wangxq10@lzu.edu.cn>,Helge Deller <deller@gmx.de>,Mateusz Guzik <mguzik@redhat.com>,Alex Thorlton <athorlton@sgi.com>,Ben Segall <bsegall@google.com>,John Stultz <john.stultz@linaro.org>,Rik van Riel <riel@redhat.com>,Eric B Munson <emunson@akamai.com>,Alexey Klimov <klimov.linux@gmail.com>,Chen Gang <gang.chen.5i5j@gmail.com>,Andrey Ryabinin <aryabinin@virtuozzo.com>,David Rientjes <rientjes@google.com>,Hugh Dickins <hughd@google.com>,Alexander Kuleshov <kuleshovmail@gmail.com>,"open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,"open list:IA64 (Itanium) PLATFORM" <linux-ia64@vger.kernel.org>,"open list:KERNEL VIRTUAL MACHINE (KVM) FOR POWERPC" <kvm-ppc@vger.kernel.org>,"open list:KERNEL VIRTUAL MACHINE (KVM)" <kvm@vger.kernel.org>,"open list:LINUX FOR POWERPC!
(32-BIT
AND 64-BIT)" <linuxppc-dev@lists.ozlabs.org>,"open list:INFINIBAND SUBSYSTEM" <linux-rdma@vger.kernel.org>,"open list:FILESYSTEMS (VFS and infrastructure)" <linux-fsdevel@vger.kernel.org>,"open list:CONTROL GROUP (CGROUP)" <cgroups@vger.kernel.org>,"open list:BPF (Safe dynamic programs and tools)" <netdev@vger.kernel.org>,"open list:MEMORY MANAGEMENT" <linux-mm@kvack.org>
Message-ID: <D79806FE-E6B9-481B-8AA2-A1800419D9B5@zytor.com>

On July 15, 2016 6:59:56 AM PDT, Peter Zijlstra <peterz@infradead.org> wrote:
>On Fri, Jul 15, 2016 at 01:52:48PM +0000, Topi Miettinen wrote:
>> On 07/15/16 12:43, Peter Zijlstra wrote:
>> > On Fri, Jul 15, 2016 at 01:35:47PM +0300, Topi Miettinen wrote:
>> >> Hello,
>> >>
>> >> There are many basic ways to control processes, including
>capabilities,
>> >> cgroups and resource limits. However, there are far fewer ways to
>find out
>> >> useful values for the limits, except blind trial and error.
>> >>
>> >> This patch series attempts to fix that by giving at least a nice
>starting
>> >> point from the highwater mark values of the resources in question.
>> >> I looked where each limit is checked and added a call to update
>the mark
>> >> nearby.
>> >
>> > And how is that useful? Setting things to the high watermark is
>> > basically the same as not setting the limit at all.
>>
>> What else would you use, too small limits?
>
>That question doesn't make sense.
>
>What's the point of setting a limit if it ends up being the same as
>no-limit (aka unlimited).
>
>If you cannot explain; and you have not so far; what use these values
>are, why would we look at the patches.

One reason is to catch a malfunctioning process rather than dragging the whole system down with it. It could also be useful for development.
--
Sent from my Android device with K-9 Mail. Please excuse brevity and formatting.

\
 
 \ /
  Last update: 2016-07-15 23:41    [W:0.052 / U:0.360 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site