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Re: pegasosII hung with new kernel - page daemon spinning



On 09/23/2012 10:19 AM, matthew green wrote:
>>>> That's interessting what size does the arena have on the system with
>>>> 512mb? Probably limited by NKMEMPAGES_MAX_DEFAULT, so it might need to
>>>> be larger on those.
>>>
>>> i noticed macppc already defines this to 256MB.  trying that now.
>>>
>>>
>>> .mrg.
>>>
>>
>> Yes, that's what I think. Having the limit at 1/3 of the kernel address
>> space size make sense.
>>
>> I don't know for sure but the kernel address space and user address
>> space on powerpc are disjunct right? So we are not really limited at all
>> like on i386.
> 
> KVA on ppc is limited to 512MB i am told.  would you then
> recommend more like 170MB?
> 
> this works, though there was a long long pause i thought there
> was a problem why my build was running though GCC.  that's a
> different issue, though again it was the page daemon cpu
> spinning for a long time.  i wonder if it should sleep for a
> second if it has looped more than N times in a row without 
> entering the wait section of the loop.  for N=1000 maybe?
> 
> 
> .mrg.
> 

ah I see we have 2 segments for the kernel, going to high here will most
likely limit the memory for uareas.
I would suggest give it a try with 200mb and see if the arenas free
memory drops below 10%.

Lars


-- 
------------------------------------

Mystische Erklärungen:
Die mystischen Erklärungen gelten für tief;
die Wahrheit ist, dass sie noch nicht einmal oberflächlich sind.

   -- Friedrich Nietzsche
   [ Die Fröhliche Wissenschaft Buch 3, 126 ]


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