Re: [Gems-users] How many hops a cache-to-cache transfer requires in MSI-MESI-CMP_directory protocol?

[Mike Marty <mikem@xxxxxxxxxxx>]

The MOESI_CMP_directory protocol does what you want: L1a->L2->L1b->L1a.

--Mike


> Hi:
>  It seems a L1 cache-to-cache transfer (on the same chip) in
> MSI-MESI-CMP_directory needs 4 hops (L1a->L2->L1b->L2->L1a) instead of
> typcial 3 hops (L1a->L2->L1b->L1a). Do you guys assume there are no
> point-to-point connection between L1s on the same chip?
>  I want to simulate a CMP with 16 cores(procs+L1s) on the same chip. All
> cores share the same L2 cache and maintain coherence by using MESI directory
> protocol with 3 hop cache-to-cache transfer. What's the most similar
> protocol available?
>  Thanks a lot!
> Legion
>