StackThreads/MP: version 0.77 User's Guide

7.3: Command Line Options Common for All StackThreads/MP Programs

Any StackThreads/MP program accepts the following command line arguments. A shorter synonym is provided for commonly used ones. These command line arguments are effective only when you do not write your own main function but write st_main.

• --n_workers P, or -nw P : specifies the number of processors by P.
• --stack_size S, or -ss S : specifies the stack size of an OS-thread by S. S is either an integer, or an integer followed by a k or m, which says the number should be interpreted as kilobytes and megabytes, respectively. For example, -ss 4m sets a stack size to 4 megabytes.
• --print_toplevel_worker_stat, or -ps : prints a simple statistics after a run. It prints statistics like how many threads were created and how many blocking occurred.
• --time_profile, or -tp : profiles processor status and generates log files. The file names begin with 00stprof by default. This can be changed by --time_profile_filename below.
• --time_profile_filename N : specifies the prefix of log files by N. For example, --time_profile_filename my_important_logs generate files of names my_important_logs.xx.yy where xx and yy are numbers.
• --time_profile_resolution S : specifies the resolution of the profile. S is the length of a period in microseconds. Each period is represented by a state in which a processor spends its longest time during that period.
• --time_profile_buffer_size N : specifies the size of in-memory buffer size of each processor. N is the number of entries in the log file. Longer the N is, each processor can tolerate a long profiling run without saving the log into a secondary storage.

These command line arguments are removed from the command line before entering st_main and only remaining arguments are passed to st_main. For example, when you write:

        ./fib -nw 10 30 -ps

        { "./fib" "30" }

parameter argc.