Re: hot and cold pages

["Martin J. Bligh" <mbligh@aracnet.com>]

>   I have a small question regarding 'per_cpu_pages' . What is
> significance if maintaining 'hot' pages and 'cold' pages list. Are hot
> pages something to do with L2 cache (on x86) ?

Yup, pages that are thought to be L2 cache hot (or cold, respectively) for
that CPU as a lifo stack.

> After going through code, I found out, any new page allocation (for file
> read)is from cold page list and zero order pages are generally freed to
> hot page list

Right ... if you're going to DMA into it, you might as well use a cold page
- no advantage to using a hot one. Pages newly freed stand a good chance of
being hot, so they're put into the hot list.

M.

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