Re: 2.4: why is NR_GFPINDEX so large?

Andrea Arcangeli
2000-06-23T18:11:09Z

On Thu, 22 Jun 2000, Kanoj Sarcar wrote:

>Umm, careful. If you happen to share a cacheline between a readonly array
>and a frequently updated variable, it might be better not to delete
>unused elements from an array - that way, you might be able to bunch up
>all the frequently updated variables into their own cacheline, and save
>the memory write back of an extra cacheline.

I think on UP we shouldn't protect any read-only memory against somebody
that isn't optimized. I think if there are a set of frequently updated
variables, _they_ should care to live in the same cacheline (and they
could also include in the same cacheline other stuff of course). It
shouldn't be the gfpmask_zone array (that is read only) that cares to not
include other stuff because there could be something not well optimized
for cacheline flushes.

>BTW, this is all of course nitpicking.

Oh indeed but it's fun ;-)

Andrea