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From: Igor Shmukler <shmukler@mail.ru>
To: Bao Zhao <baozhaolinuxer@yahoo.com>
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Subject: Re[2]: relation between PQ_CACHESIZE and PQ_L2_SIZE
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> http://lists.freebsd.org/mailman/htdig/freebsd-hackers/2003-June/001655.html
>    But what puzzled me is : why not page size is  a 
> factor when calculating the number of colors?

Page coloring in freebsd was implemented by John Dyson. It is needed to better utilize the 
cache. Depending on cache's implementation fully-associative vs. 4-way vs 2-way etc you might 
have problems.

A subset of bits (low-bits) from the page frame's (physical) address tells us where can data be 
stored in processor cache. We want a relatively equal distribution of these "colors" so that we 
utilize as much of cache real estate as possible. Hence, we are interested in the size of a 
set, not size of a page.

I am sure, there are whole bunch of articles written about this. I could give you some pointers 
offline.

Igor.