#SYNCHROTRACE

There are two tools which together form the prototype SynchroTrace simulation flow built into Gem5. 1) Sigil - Multi-threaded Trace Capture Tool 2) Replay - Event-Trace Replay Framework

This code base includes (2) Replay. Currently, the Sigil version required to generate traces is provided separately from the same github user "dpac-vlsi".

The logical steps to using this simulation environment for design space exploration or CMP simulation is as follows: 1) a) Generate Multi-threaded Event Traces for the program binary you are testing (See Sigil documentation for further information): -Use the Sigil wrapping script (runsigil_and_gz_newbranch.py) with necessary options on your binary OR b) Use previously generated or sample traces 2) Compile SynchroTrace (For a list of dependencies, please look in the Additional Notes section below) 3) Run SynchroTrace with necessary options on the generated traces

#####Installing SynchroTrace and Running the 8 Thread FFT Example

1. Check Necessary Dependencies: gcc-4.4.7 gmp-5.1.1 mpc-1.0 mpfr-3.1.2 swig-2.0.1 python-2.7.6 scons-2.3.0 zlib-dev or zlib1g-dev m4

   • Please note: a) Runtime problems have been encountered when using later versions of swig and gcc.

   b) Please ensure /usr/bin/gcc-4.4 is symbolically linked to your defaultgcc (/usr/bin/gcc)

   c) gmp, mpc, and mpfr are packaged with gcc when using package installer such as apt.

   d) swig-2.0.1 can be found at http://sourceforge.net/projects/swig/files/swig/swig-2.0.1/

   e) Currently we do not provide any means to automatically install the missing packages.

2. Build SynchroTrace

a) If not done so, clone the SynchroTrace repo from GitHub:

$ git clone https://github.com/dpac-vlsi/SynchroTrace

b) Go to the base SynchroTrace directory

c) Run the following command (Note that the number of jobs refers to the number of cores available for compilation):

     scons build/X86_MESI_CMP_directory/gem5.opt --jobs=6

At this point, the gem5 executable should be built with integrated Trace Replay in the location specified in the command above.

gem5 is usually run with a configuration script that hooks up the various architecture models packaged with the gem5 framework. We have written a SynchroTrace configuration script to which arguments can be passed to configure the desired system.

This script can be found at <SYNCHROTRACE_FOLDER>/configs/synchrotrace/synchrotrace.py

The run_synchrotrace_fft.pl run script can be used to run the FFT example simply as follows:

$ ./run_synchrotrace_fft.pl

This script can be modified and emulated to run your own configuration. A different trace location by changing the $eventDir variable. This design being simulated is set by changing the arguments provided in the $synchrotracecmd variable. For a list of valid arguments, run the following from the main SynchroTrace folder:

$ ./build/X86_MESI_CMP_directory/gem5.opt ./configs/synchrotrace/synchrotrace.py --help

d) Once the run is completed, simulated metrics can be found in m5out/stats.txt and m5out/ruby.stats

#################################################################################################################################### #####Additional Notes:

1. Sample Sigil Traces are located in $BASESYNCHROTRACEDIR/sample_sigil_traces

2. SynchroTrace configurations are located in $BASESYNCHROTRACEDIR/configs/synchrotrace/synchrotrace.py and $BASESYNCHROTRACEDIR/configs/ruby/Ruby.py

3. The run_synchrotrace_fft.pl run script has a section for debug flags. The following is a list of the available debug flags used by SynchroTrace with brief descriptions.

   -DebugFlag('mutexLogger') - Prints order of threads obtaining mutex lock

   -DebugFlag('printEvent') - Prints EventID# for specific thread before/after event started/completed. This debug flag makes the simulation time very slow.

   -DebugFlag('printEventFull') - Prints EventIDs for Threads, Threads on what Cores every 50k cycles

   -DebugFlag('cacheMiss') - Prints out cache misses as they happen and address

   -DebugFlag('memoryInBarrier') - prints memory reads, writes, read bytes, write bytes every barrier

   -DebugFlag('flitsInBarrier') - prints flits generated every barrier

   -DebugFlag('l1MissesInBarrier') - prints l1 misses per thread every barrier

   -DebugFlag('latencyInBarrier') - prints 3 lines. # packets in barrier, Accumulated queueing delay in barrier, Accumulated network latency in Barrier.

   -DebugFlag('powerStatsInBarrier') - prints the total router power specifically for that barrier, i.e. not a rolling average.

   -DebugFlag('roi') - Prints out the cycle when we reach the parallel region in Debate. Prints out when the threads all join up.

   -DebugFlag('netMessages') - Prints the network packet messages out at 10k cycle buckets.

   -DebugFlag('amTrace') - Original default debug flag.

4. An example of this command with a debug flag is as follows:

./build/X86_MESI_CMP_directory/gem5.opt --debug-flags=printEventFull ./configs/synchrotrace/synchrotrace.py --garnet-network=fixed --topology=Mesh --mesh-rows=8 --eventDir=$eventDir --outputDir=$outputDir --num-cpus=8 --num_threads=8 --num-dirs=8 --num-l2caches=8 --l1d_size=8kB --l1d_assoc=16 --l1i_size=8kB --l1i_assoc=2 --l2_size=128kB --l2_assoc=4 --cpi_iops=1 --cpi_flops=2 --bandwidth_factor=4 --l1_latency=3 --masterFreq=1 2> fft.err";

where the $eventDir points to the directory of the traces and $outputDir points to the desired output directory path.