"Virtually indexed, physically tagged" cache is one of best suited
machinary for UNIX type compuer system. 
If you have a chance to buy and read one particular book, you will
get a complete picture all about the cache issues.  Story is long but
very satisfying.

UNIX Systems for Modern Architectures; Symmetric Multiprocessing
and Caching for Kernel Programmers
Curt Schimmel ISBN 0-201-63338-8

You will never regret to get it as long as you're concerned with kernel
programming.

Toru Nishimura

> From: Raj Raman <the_raj_raman@hotmail.com>
> List: port-mips
> Date: 03/11/2002 19:15:20 
> Hi All,
>
> I belive the implementation of cache in R4000 that uses virtual address for 
> indexing and physical address for tagging.
> What are the advantages of indexing with virtual address _vs_ physical 
> address ?
>
> Would appreciate some clarity.
>
> Thanks,
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