Hi all,
I am working with gem5 and ruby in order to measure the link utilization of the 
interconection network that connects my cores and caches. I have some trouble 
understanding the parameters that define the bandwidth of each link.
I am using simple links (NOT garnet) and from the wiki page I gathered that the 
bandwidth of the link is defined as endpoint_bandwidth*bandwidth_factor. That 
is done in the Throttle.hh file. The bandwidth_factor is defined at 
BasicLink.py and the endpoint_bandwidth at SimpleNetwork.py.
Now my question is about those 2 parameters and what they represent. In my 
understanding bandwidth_factor defines the width of my link (how many bytes can 
fit) and it has a default value of 16bytes. However I have no idea of what the 
purpose of endpoint_bandwidth is or what it actually represents. The only thing 
I could find is that is an "adjustment factor" and its default value is 1000. 
Does it have to do with frequency? Does Throttle wakes up every 1000 cycles?
I did some experiments and noticed that my links utilization is analogues to 
the bandwidth_factor, meaning that if i cut bandwidth factor in half my 
utilization roughly doubles. Although endpoint_bandwidth also changes my 
utilization I could not see a specific pattern.
For my work is important to provide realistic link bandwidth and so my 
questions is what endpoint_bandwidth represents and what is a realistic value 
for it?
Thanks!George                                     
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