Re: [PATCH 0/8] idle page tracking / working set estimation

Balbir Singh
2011-09-27T16:57:02Z

>>
>> Sorry, I have trouble parsing this sentence, could you elaborate on "when"?
>
> page_referenced() indicates if a page was accessed since the previous
> page_referenced() call.
>
> page_referenced_kstaled() indicates if a page was accessed since the
> previous page_referenced_kstaled() call.
>
> Both of the functions need to clear PTE young bits; however we don't
> want the two functions to interfere with each other. To achieve this,
> we add two page bits to indicate when a young PTE has been observed by
> one of the functions but not by the other.

OK and this gives different page aging schemes for the same page? Is
this to track state changes

PR1 sees: PTE x young as 0
PR2 sees: PTE x as 1, the rest to 0

so PR1 and PR2 will disagree? Should I be looking deeper in the
patches to understand

Balbir