Re: [Gems-users] Some Problems about the MOESI_directory cache coherence protocol

[Nilay Vaish <nilay@xxxxxxxxxxx>]

On Wed, 13 Jul 2011, sheng ma wrote:

> Hi, I am a newer to the GEMS simulator. I am interested in the
> MOESI_directory cache coherence protocol. I have several questions about the
> implementation codes.
> 1. When I reading the MOESI_directory-cache.sm file, I noticed there are
> some words like "GetX", "GetS" and "PUT", and I am wondering what is the
> particular meaning of these words?
> "GETS" = "GET shared"?? "GETX" = "GET exclusived"?? I am not sure about it,
> especially what is the particular meaning of "PUT"?
> 2. Because I am not very familiar with the MOESI_directory protocol, I want
> to know which kind of message will be sent to multiple destinations? I know
> the invalidate message maybe needed to send to multiple destinations. But I
> am not sure whether there are still other message types need to send to
> multiple destinations?
> 3. Whether the invalidation message are always forwarded by the directory
> node?
>
> Thank you!
Coherence protocol implementations available in gem5 have been documented 
here --
http://gem5.org/Cache_Coherence_Protocols

--
Nilay