This is the command threadscope that can be run in the OnWorks free hosting provider using one of our multiple free online workstations such as Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator
PROGRAM:
NAME
threadscope - a graphical thread profiler for Haskell GHC programs
SYNOPSIS
threadscope [program.eventlog]
DESCRIPTION
Threadscope is a graphical thread profiler for Haskell programs.
It parses and displays the content of .eventlog files emitted by the GHC 6.12.1 and later
runtimes, showing a timeline of spark creation, spark-to-thread promotions and garbage
collections.
This helps debugging the parallel performance of Haskell programs, making easier to check
that work is well balanced across the available processors and spot performance issues
relating to garbage collection or poor load balancing.
ARGUMENTS
threadscope takes the name of the GHC RTS event-log file to process as its single
argument. If no filename is given, threadscope starts with an empty workspace, where any
event-log file can be loaded by means of the GUI file browser facilities.
USAGE
In order for threadscope to be useful, you have to compile your Haskell program to use
GHC's threaded run-time and also to create runtime profile logs. This can be accomplished
with the following command line options to ghc(1)
$ ghc -threaded -eventlog --make Foo.hs -o foo
Once the program is built, execute it using the multithreaded run-time, specifying the
number of HECs (Haskell Execution Contexts) to use in the usual manner, but also
requesting the creation of an event log. For example, to use two HECs and create an event
log you would use
$ foo +RTS -N2 -ls -RTS ...
Once the program runs to completion, a file named foo.eventlog is produced. You can start
threadscope from the shell prompt passing the event-log filename as the single argument,
or you can start threadscope from the desktop menus and use its file browsing capabilities
to find and open it.
Use threadscope online using onworks.net services
