> On June 2, 2015, 11:58 p.m., Brad Beckmann wrote:
> > Any more comments on this patch?

Oops...I just noticed on 5/20 Nilay wrote "I think the aim of stall and wait 
functionality was to look beyond the message that is at the head of the 
priority queue.  While earlier we were attaching some delay with moving 
messages around, this patch does away with that delay.  I no longer see the 
point of moving messages from one structure to another.  I suggest that we 
remove the whole stall and wait approach and replace the priority queue in the 
message buffer with either std::list or std::set.  The code will be way more 
simple."

The delay moving messages around was not intended to model real hardware delay. 
 The delay was a mistake and allowed messages to get out-of-order. The slicc 
SMs are written with the expectation that the message buffers maintain ordering 
when possible.  It is important to performance that they do so.  std::list or 
std::set do not maintain ordering.  If we were to make that change, I suspect 
it would have a negative impact on performance.


- Brad


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On May 26, 2015, 8:03 p.m., Tony Gutierrez wrote:
> 
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> http://reviews.gem5.org/r/2805/
> -----------------------------------------------------------
> 
> (Updated May 26, 2015, 8:03 p.m.)
> 
> 
> Review request for Default.
> 
> 
> Repository: gem5
> 
> 
> Description
> -------
> 
> Changeset 10835:e6fd9419eacf
> ---------------------------
> ruby: Fix for stallAndWait bug
> 
> It was previously possible for a stalled message to be reordered after an
> incomming message. This patch ensures that any stalled message stays in its
> original request order.
> 
> 
> Diffs
> -----
> 
>   src/mem/ruby/network/MessageBuffer.cc 
> df2aa91dba5b0f0baa351039f0802baad9ed8f1d 
>   src/mem/ruby/slicc_interface/AbstractController.hh 
> df2aa91dba5b0f0baa351039f0802baad9ed8f1d 
>   src/mem/ruby/slicc_interface/AbstractController.cc 
> df2aa91dba5b0f0baa351039f0802baad9ed8f1d 
> 
> Diff: http://reviews.gem5.org/r/2805/diff/
> 
> 
> Testing
> -------
> 
> 
> Thanks,
> 
> Tony Gutierrez
> 
>

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