Re: [PATCH] 2/2 Prezeroing large blocks of pages during allocationVersion 4

[KAMEZAWA Hiroyuki]

Mel Gorman wrote:

> > >      
> > Now, 5bits per  MAX_ORDER pages.
> > I think it is simpler to use "char[]" for representing type of  memory alloc
> > type than bitmap.
> >
> >    
>
> Possibly, but it would also use up that bit more space. That map could be
> condensed to 3 bits but would make it that bit (no pun) more complex and
> difficult to merge. On the other hand, it would be faster to use a char[]
> as it would be an array-index lookup to get a pageblock type rather than a
> number of bit operations.
>
> So, it depends on what people know to be better in general because I have
> not measured it to know for a fact. Is it better to use char[] and use
> array indexes rather than bit operations or is it better to leave it as a
> bitmap and condense it later when things have settled down?
>  
Hmm, Okay, I'll wait for condensed version.
BTW, in space consumption/cache view,  does using bitmap have  real 
benefit   ?

Thanks
-- Kame <kamezawa.hiroyu@xxxxxxxxxxxxxx>

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