Re: [PATCH] Pentium IV cacheline size.

[Manfred Spraul <manfred@colorfullife.com>]

 
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Linus wrote:
> On Sat, 13 Oct 2001, Dave Jones wrote:
> >
> > Currently, we're using a L1_CACHE_SHIFT value of 7
> > for Pentium 4, which equates to 128 byte cache lines.
> 
> Well, the fact is, that from a SMP standpoint, the 128 bytes is the
> correct one: the L2 is 128 bytes wide.

The 128 bytes are split into 2 sectors - I'm not sure if 128 or 64 bytes
is appropriate.

<<<<<
The L2 cache is a 256K-byte cache that holds both instructions
that miss the Trace Cache and data that miss the L1 data cache.
The L2 cache is organized as an 8-way set-associative cache with
128 bytes per cache line. These 128-byte cache lines consist of
two 64-byte sectors. A miss in the L2 cache typically initiates
two 64-byte access requests to the system bus to fill both halves
of the cache line.
<<<<<
http://developer.intel.com/technology/itj/q12001/articles/art_2.htm

--
	Manfred