Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1265381

Re: Question with maxcpus= parameter.

From Zhenzhong Duan <zhenzhong.duan@oracle.com>
Newsgroups linux.kernel
Subject Re: Question with maxcpus= parameter.
Date 2015-11-09 06:50 +0100
Message-ID <qsNv5-2fT-27@gated-at.bofh.it> (permalink)
References <qrHL4-ha-1@gated-at.bofh.it> <qsNv5-2fT-29@gated-at.bofh.it>
Organization Oracle

Show all headers | View raw


Tried nr_cpus=4, works.

[root@rwssq01 ~]# cat /sys/devices/system/cpu/possible
0-3
[root@rwssq01 ~]# cat /sys/devices/system/cpu/present
0-3
[root@rwssq01 ~]# uname -a
Linux rwssq01.us.oracle.com 3.8.13-44.1.1.el6uek.x86_64 #2 SMP Wed Sep 
10 06:10:25 PDT 2014 x86_64 x86_64 x86_64 GNU/Linux

zduan
在 2015/11/7 0:14, Konrad Rzeszutek Wilk 写道:
> On Fri, Nov 06, 2015 at 01:24:16PM +0800, Zhenzhong Duan wrote:
>> Hi Maintainers,
>>
>> Recently we faced an cpu online issue with maxcpus= parameter.
> Did you try 'nr_cpus' ?
>> We want to have 4 cpus onlined at bootup, test 3.8.13-stable on an 72 cpus
>> env with maxcpus=4, I found more cpus than 4 are onlined.
>> It's the udev scripts make them onlined. But below script exist for a long
>> time.
>> ACTION=="add", KERNEL=="cpu[0-9]*", RUN+="/bin/bash -c 'echo 1 >
>> /sys/devices/system/cpu/%k/online'"
>>
>> maxcpu= parameter didn't take effect, so is this a kernel bug? Or that
>> script should be removed?
>>
>> Btw: 2.6.39 works fine, I checked udev log, seems CPU ADD event is only sent
>> for 4cpus.
>> Why the difference between 2.6.39 and 3.8.13?
>>
>> thanks
>> zduan

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

Question with maxcpus= parameter. Zhenzhong Duan <zhenzhong.duan@oracle.com> - 2015-11-06 06:30 +0100
  Re: Question with maxcpus= parameter. "Raj, Ashok" <ashok.raj@intel.com> - 2015-11-06 07:00 +0100
    Re: Question with maxcpus= parameter. Zhenzhong Duan <zhenzhong.duan@oracle.com> - 2015-11-06 07:30 +0100
  Re: Question with maxcpus= parameter. Zhenzhong Duan <zhenzhong.duan@oracle.com> - 2015-11-09 06:50 +0100
    Re: Question with maxcpus= parameter. Yinghai Lu <yinghai@kernel.org> - 2015-11-09 07:20 +0100
      Re: Question with maxcpus= parameter. Zhenzhong Duan <zhenzhong.duan@oracle.com> - 2015-11-09 10:10 +0100
        Re: Question with maxcpus= parameter. Yinghai Lu <yinghai@kernel.org> - 2015-11-09 18:10 +0100

csiph-web