> > Thanks.
> > yes, actually It stalls (not recycle) the the mandatory queue. I guess
> > this is for in order requirement (mandatory queue is a FIFO). right?
>
> MOESI_CMP_directory uses recycles instead so that other mandatory queue
> requests can be processed while one is stalled.
>
> I would think the same thing could (and should) be done for
> MSI_MOSI_CMP_directory.
>
On the other hand, the only time a request is stalled in the mandatory
queue is if something else is already going on for the same block (like a
replacement, or a conflicting request for the same block address). This
should be very rare, so MLP (memory-level parallelism) is not really
impacted by this implementation decision of using z_stall.
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