Re: [PATCH 0/9] V2: idle page tracking / working set estimation

Eric B Munson
2011-09-30T21:41:14Z

On Fri, 30 Sep 2011 14:16:25 -0700, Michel Lespinasse wrote:
> On Fri, Sep 30, 2011 at 11:19 AM, Eric B Munson <emunson@mgebm.net>
> wrote:
>> I am able to recreate on a second desktop I have here (same model
>> CPU but a
>> different MB so I am fairly sure it isn't dying hardware).  It looks
>> to me like
>> a CPU softlocks and it stalls the process active there, so most
>> recently that
>> was XOrg.  The machine lets me login via ssh for a few minutes, but
>> things like
>> ps and cat or /proc files will start to work and give some output
>> but hang.
>> I cannot call reboot, nor can I sync the fs and reboot via SysRq.
>>  My next step
>> is to setup a netconsole to see if anything comes out in the syslog
>> that I
>> cannot see.
>
> I haven't had time to try & reproduce locally yet (apologies - things
> have been coming up at me).
>
> But a prime suspect would be a bad interaction with
> CONFIG_MEMORY_HOTPLUG, as Kamezama remarked in his reply to patch 4.
> I
> think this could be the most likely cause of what you're observing.

I will try disabling Memory Hotplug on Monday and let you know if that
helps.

Eric