From GEM5 Statistics to McPAT Input

This repository contains a script to convert GEM5 simulation statistics to McPAT compatible inputs.

My Notes

• Create description file python2 GEM5ToMcPAT.py my_STATS/base/canneal_simsmall_64_0 templates/template-xeon_my_4_4.xml
• Run (TODO) python2 run_extract.py base_canneal_simsmall_64_0_4_4 base_canneal_simsmall_64_0_4_8

Quick Start

Use the following command to invoke the script:
GEM5ToMcPAT.py [options] <gem5 stats file> <gem5 config file (json)> <mcpat template file>

For more options, please run:
GEM5ToMcPAT.py -h

Example

This repository contains a sample GEM5 generated stats file, a processor configuration file produced by GEM5 and a McPAT template file. To run GEM5ToMcPAT.py use:
GEM5ToMcPAT.py stats.txt config.json template-xeon.xml

The above command will produce mcpat-out.xml file. mcpat-out.xml can be used in the usual way with McPAT.
<mcpat-bin> -infile mcpat-out.xml

Internals

###Preparing Template File The above example uses a template file created by modifying ProcessorDescriptionFiles/Xeon.xml from McPAT. The parameters in Xeon.xml that should get their value from GEM5 configuration (config.json) should be replaced with config.<parameter_path>. Please take a look at the template-xeon.xml to get the hang of it. For example,
<param name="number_hardware_threads" value="2"/>
should be replaced by
<param name="number_hardware_threads" value="config.system.cpu.numThreads"/>
in the template file.

Any standard computation in python-supported format is allowed. For example, the following is acceptable:
<param name="target_core_clockrate" value="1e-6/config.system.cpu_clk_domain.clock"/><!--MHz -->

Similarly, statistics that should use values from GEM5 statistics (stats.txt) should be replaced with stats.<stat_path>. For example,
<stat name="total_cycles" value="100000"/>
should be replaced by
<stat name="total_cycles" value="stats.system.cpu.numCycles"/>
in the template file.

###Modifying Script The workhorse function of the script is dumpMcpatOut. It first replaces all the config parameters by using the values from config.json and subsequently works on stats parameters. This is the place to fix things if anything does not work for you.

Miscellaneous

These scripts are inspired by m5-mcpat.pl script but implemented in python instead of perl.