Hi,

I am trying to run multi-threaded benchmarks using SMT on the SE mode of 
gem5.


To start off, I used the command (this is multi-program) -
build/X86/gem5.fast configs/example/se.py --ruby --smt -c 'tests/test-
progs/hello/bin/x86/linux/hello;tests/test-progs/hello/bin/x86/linux/hello'

This gives me errors in the x86 case -

dependGraph[502]: No producer. consumer:
dependGraph[503]: No producer. consumer:

and aborts.

I found this error discussed in some earlier posts as well and I don't know 
if there have been any updates (this is the latest gem5 version). So does 
this mean I cannot perform SMT in X86 mode?

My main error I am trying to debug (may be related to the above too) is -

I have a program that creates n number of threads based on a parameter 
passed and I have statically compiled this and linked with the M5 Threads 
etc.

When I run the command, "build/X86/gem5.fast configs/example/se.py --ruby -n 
3 -cpu_type=detailed -c ../programs/eg_pthread -o "2"" - 
I get the expected output. I am in need of 3 cores (number of threads + 1) 
and this works fine.

Now I want to try this in the smt mode - I want to have 1 core and have 2 
(or 3?) threads to do the above process. So my command becomes -

"build/X86/gem5.fast configs/example/se.py --ruby -n 1 --smt -
cpu_type=detailed -c ../programs/eg_pthread -o "2""

In this case I get the error "Called sys_clone, but no unallocated thread 
contexts found"

To debug this, inside the se.py, if I print the value of numThreads, I see 
it to be 1. Should this be 2(or 3?) in my case?

If I get the numThreads right I think I would still need to do something 
like "system.cpu[i].workload = [ multiprocesses[0]] * int(numThreads)" which 
is discussed at http://en.it-usenet.org/thread/11778/10994/ but since I'm 
having issues with the number of threads I'm not sure how to proceed.

In summary, I basically want to know how do I run a single program that has 
multiple threads (say a Parsec benchmark) on a single core in SE mode using 
SMT. I am currently experimenting on X86 but I am open to using any ISA.

Any help would be appreciated since I've been stuck with this issue for 
quite a while now. 

Thanks,
Gokul










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