THREADSCOPE(1)
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.
SEE ALSO
AUTHOR
- threadscope was written by
- Simon Marlow <marlowsd@gmail.com>
Donnie Jones <donnie@darthik.com>
Satnam Singh <s.singh@ieee.org> - This manual page was written by
Ernesto Hernndez-Novich (USB) <emhn@usb.ve>- for the Debian project (and may be used by others).