[PATCH 00/14] Present useful limits to user (v2)
H. Peter Anvin
hpa at zytor.com
Sat Jul 16 06:54:44 AEST 2016
<lizefan at huawei.com>,Johannes Weiner <hannes at cmpxchg.org>,Alexei Starovoitov <ast at kernel.org>,Arnaldo Carvalho de Melo <acme at kernel.org>,Alexander Shishkin <alexander.shishkin at linux.intel.com>,Balbir Singh <bsingharora at gmail.com>,Markus Elfring <elfring at users.sourceforge.net>,"David S. Miller" <davem at davemloft.net>,Nicolas Dichtel <nicolas.dichtel at 6wind.com>,Andrew Morton <akpm at linux-foundation.org>,Konstantin Khlebnikov <koct9i at gmail.com>,Jiri Slaby <jslaby at suse.cz>,Cyrill Gorcunov <gorcunov at openvz.org>,Michal Hocko <mhocko at suse.com>,Vlastimil Babka <vbabka at suse.cz>,Dave Hansen <dave.hansen at linux.intel.com>,Greg Kroah-Hartman <gregkh at linuxfoundation.org>,Dan Carpenter <dan.carpenter at oracle.com>,Michael Kerrisk <mtk.manpages at gmail.com>,"Kirill A. Shutemov" <kirill.shutemov at linux.intel.com>,Marcus Gelderie <redmnic at gmail.com>,Vladimir Davydov <vdavydov at virtuozzo.com>,Joe Perches <joe at perches.com>,Frederic Weisbecker <fweisbec at gmail.com>,Andrea Arcangeli <aarcange at redhat.com>,!
Biederman" <ebiederm at xmission.com>,Andi Kleen <ak at linux.intel.com>,Oleg Nesterov <oleg at redhat.com>,Stas Sergeev <stsp at list.ru>,Amanieu d'Antras <amanieu at gmail.com>,Richard Weinberger <richard at nod.at>,Wang Xiaoqiang <wangxq10 at lzu.edu.cn>,Helge Deller <deller at gmx.de>,Mateusz Guzik <mguzik at redhat.com>,Alex Thorlton <athorlton at sgi.com>,Ben Segall <bsegall at google.com>,John Stultz <john.stultz at linaro.org>,Rik van Riel <riel at redhat.com>,Eric B Munson <emunson at akamai.com>,Alexey Klimov <klimov.linux at gmail.com>,Chen Gang <gang.chen.5i5j at gmail.com>,Andrey Ryabinin <aryabinin at virtuozzo.com>,David Rientjes <rientjes at google.com>,Hugh Dickins <hughd at google.com>,Alexander Kuleshov <kuleshovmail at gmail.com>,"open list:DOCUMENTATION" <linux-doc at vger.kernel.org>,"open list:IA64 (Itanium) PLATFORM" <linux-ia64 at vger.kernel.org>,"open list:KERNEL VIRTUAL MACHINE (KVM) FOR POWERPC" <kvm-ppc at vger.kernel.org>,"open list:KERNEL VIRTUAL MACHINE (KVM)" <kvm at vger.kernel.org>,"open list:LINUX FOR POWERPC!
AND 64-BIT)" <linuxppc-dev at lists.ozlabs.org>,"open list:INFINIBAND SUBSYSTEM" <linux-rdma at vger.kernel.org>,"open list:FILESYSTEMS (VFS and infrastructure)" <linux-fsdevel at vger.kernel.org>,"open list:CONTROL GROUP (CGROUP)" <cgroups at vger.kernel.org>,"open list:BPF (Safe dynamic programs and tools)" <netdev at vger.kernel.org>,"open list:MEMORY MANAGEMENT" <linux-mm at kvack.org>
Message-ID: <D79806FE-E6B9-481B-8AA2-A1800419D9B5 at zytor.com>
On July 15, 2016 6:59:56 AM PDT, Peter Zijlstra <peterz at 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
>> >> cgroups and resource limits. However, there are far fewer ways to
>> >> useful values for the limits, except blind trial and error.
>> >> This patch series attempts to fix that by giving at least a nice
>> >> point from the highwater mark values of the resources in question.
>> >> I looked where each limit is checked and added a call to update
>> >> 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.
More information about the Linuxppc-dev