The MSHR utility interfaces with splot to generate plots of the request MSHR utilization at the caches. These plots can be used to indicate overlap and contention in the system. Each plot gives the percentage of the time spent in the phase of interest (on the Y-axis) for which misses occupy at least N MSHRs, where N is the number on the X-axis. The phases understood by MSHR correspond to the cache phases of stats_miss. The maximum X-axis value is currently set to 8 in this script. Multiple simulation runs can be plotted on the same graph.
The MSHR program uses the following command line.
MSHR plotname graph1 app1_stat phase1 [graph2 app2_stat phase2] ...
plotname specifies the title of the plot. graph1 and graph2 specify the names of the individual graphs in the plot, and are used in the legend of the plot. app1_stat and app2_stat are the filenames of the detailed statistics files generated by the simulation runs being plotted. phase1 and phase2 specify the cache phase to be used for each application detailed statistics file.
The program generates two command files for the L1 and L2 MSHR utilization in the working directory called MSHR_ plotnameL1.cmd and MSHR_plotnameL2.cmd respectively, where plotname is the title of the graph specified in the command line. MSHR then runs splot on these command files to generate Postscript output files, which are displayed using ghostview.