Sub-blocking vs cache-line-overwrite (Was Re: RE: RE: [gclist] reference counting)
Fri, 15 Sep 2000 00:56:53 -0500
Jeff Sturm wrote (Fri, Sep 15, 2000 at 01:37:28AM -0400) :
> I'm not really familiar with this capability. On the other hand,
> write-allocate seems to be available with Alpha EV6, and I think I heard
> someone say MIPS and PA-RISC have it too.
I think "write-allocate" means that a write miss will allocate
a block in the cache AND fill it with previous contents, as
opposed to a write-noallocate which bypasses the cache
on a write miss (straight from Hennessy & Patterson, Chap 5).
The term we should use is something like "write-allocate-nofill",
a write miss will allocate a line but NOT fill it from memory.
Which is what the WH64 Alpha instruction does (as a hint).