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

Groups > linux.kernel > #1292722

Re: [PATCH RFC] memory-hotplug: add automatic onlining policy for the newly added memory

Show all headers | View raw

On 2015/12/16 2:05, Vitaly Kuznetsov wrote:

> Currently, all newly added memory blocks remain in 'offline' state unless
> someone onlines them, some linux distributions carry special udev rules
> like:
> 
> SUBSYSTEM=="memory", ACTION=="add", ATTR{state}=="offline", ATTR{state}="online"
> 
> to make this happen automatically. This is not a great solution for virtual
> machines where memory hotplug is being used to address high memory pressure
> situations as such onlining is slow and a userspace process doing this
> (udev) has a chance of being killed by the OOM killer as it will probably
> require to allocate some memory.
> 
> Introduce default policy for the newly added memory blocks in
> /sys/devices/system/memory/hotplug_autoonline file with two possible
> values: "offline" (the default) which preserves the current behavior and
> "online" which causes all newly added memory blocks to go online as
> soon as they're added.
> 
> Cc: Jonathan Corbet <corbet@lwn.net>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Daniel Kiper <daniel.kiper@oracle.com>
> Cc: Dan Williams <dan.j.williams@intel.com>
> Cc: Tang Chen <tangchen@cn.fujitsu.com>
> Cc: David Vrabel <david.vrabel@citrix.com>
> Cc: David Rientjes <rientjes@google.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
> Cc: Gu Zheng <guz.fnst@cn.fujitsu.com>
> Cc: Xishi Qiu <qiuxishi@huawei.com>
> Cc: Mel Gorman <mgorman@techsingularity.net>
> Cc: "K. Y. Srinivasan" <kys@microsoft.com>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
> ---
> - I was able to find previous attempts to fix the issue, e.g.:
>   http://marc.info/?l=linux-kernel&m=137425951924598&w=2
>   http://marc.info/?l=linux-acpi&m=127186488905382
>   but I'm not completely sure why it didn't work out and the solution
>   I suggest is not 'smart enough', thus 'RFC'.

+ CC: 
yanxiaofeng@inspur.com
liuchangsheng@inspur.com

Hi Vitaly,

Why not use udev rule? I think it can online pages automatically.

Thanks,
Xishi Qiu

--
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 | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH RFC] memory-hotplug: add automatic onlining policy for the newly added memory Vitaly Kuznetsov <vkuznets@redhat.com> - 2015-12-15 19:10 +0100
  Re: [PATCH RFC] memory-hotplug: add automatic onlining policy for  the newly added memory Daniel Kiper <daniel.kiper@oracle.com> - 2015-12-16 00:00 +0100
    Re: [PATCH RFC] memory-hotplug: add automatic onlining policy for the newly added memory Vitaly Kuznetsov <vkuznets@redhat.com> - 2015-12-16 10:30 +0100
  Re: [PATCH RFC] memory-hotplug: add automatic onlining policy for  the newly added memory Xishi Qiu <qiuxishi@huawei.com> - 2015-12-16 04:30 +0100
    Re: [PATCH RFC] memory-hotplug: add automatic onlining policy for the newly added memory Vitaly Kuznetsov <vkuznets@redhat.com> - 2015-12-16 10:20 +0100
      Re: [PATCH RFC] memory-hotplug: add automatic onlining policy for  the newly added memory Xishi Qiu <qiuxishi@huawei.com> - 2015-12-16 11:50 +0100
        Re: [PATCH RFC] memory-hotplug: add automatic onlining policy for the newly added memory Vitaly Kuznetsov <vkuznets@redhat.com> - 2015-12-16 12:00 +0100

csiph-web