On 10/14/07, shyam Burkule <[EMAIL PROTECTED]> wrote:
>
>
>
> On 10/13/07, Peter Teoh <[EMAIL PROTECTED]> wrote:
> >
> > I think I have understood better.
> >
> > On 10/13/07, shyam Burkule < [EMAIL PROTECTED]> wrote:
> > > Hi
> > >     Now as given in fig. if there is second reference
> > mark_page_accessed()
> > > will invoke and then change flag PG_referenced to 1 and still page is
> > in
> > > inacive list.Is it really true...i mean at this point of reference
> > there
> > > will be cache hit and therefore controll doesnt comes to kernel.
> > > And also as i think this set of PG_referenced is very important.So if
> > it is
> > > not true then what and how  LRU moves pages across its inactive and
> > active
> > > list.
> >
> > See:
> >
> > http://kernel.org/doc/gorman/html/understand/understand013.html
> >
> > Ok, from diagram, inactive->active is done in shrink_cache().
>
>
>
>  This is point of question ....When page is in inactive list and if any
> process trying to access page ,there will be cache hit.And In practice we
> simple cannot modify LRU list on cache hit...so is it really true that then
> function() is get called when there is reference to page,when it is in
> inactive list?? If not then when page is moved from inactive to active
> list?.
>
>
> active->inactive is done in refill_inactive().
> >
> > Please read in depth 10.3.2 and 10.3.1.   ALl the answer is there.
> >
> > In particular this line:
> >
> > >>>From there, the function is basically a very large for-loop which
> > scans at most max_scan pages to free up nr_pages pages from the end of
> > the inactive_list or until the inactive_list is empty.  After each
> > page, it checks to see whether it should reschedule itself so that the
> > swapper does not monopolise the CPU.
> >
> > And so I think the timing in non-deterministic, because if schedule()
> > can be called after every page move from inactive_list to active_list,
> > then there is no timing at all.
> >
>
>
>
> --
> Shyam
>   "Born To Learn"




-- 
Shyam
  "Born To Learn"

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