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Diffstat (limited to 'ghc/docs/users_guide/parallel.lit')
| -rw-r--r-- | ghc/docs/users_guide/parallel.lit | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/ghc/docs/users_guide/parallel.lit b/ghc/docs/users_guide/parallel.lit index 335e8febcf..b01dec5eb0 100644 --- a/ghc/docs/users_guide/parallel.lit +++ b/ghc/docs/users_guide/parallel.lit @@ -487,11 +487,14 @@ The above will create files named \tr{<something>.prof} and/or \tr{<something>.time} {\em in your home directory}. You can process the \tr{.time} files into PostScript using \tr{hp2ps}, \index{hp2ps} -as described elsewhere in this guide. The only thing is: -because of the weird file names, you probably need to use -\tr{hp2ps} as a filter; so: +as described elsewhere in this guide. + +Because of the weird file names, you probably need to use +\tr{hp2ps} as a filter. Also, you probably want to give \tr{hp2ps} +a \tr{-t0} flag, so that no ``inconsequential'' data is ignored---in +parallel-land it's all consequential. So: \begin{verbatim} -% hp2ps < fooo.001.time > temp.ps +% hp2ps -t0 < fooo.001.time > temp.ps \end{verbatim} %$$ The first line of the @@ -539,6 +542,21 @@ because of the weird file names, you probably need to use %************************************************************************ %* * +\subsubsection{Other useful info about running parallel programs} +%* * +%************************************************************************ + +The ``garbage-collection statistics'' RTS options can be useful +for seeing what parallel programs are doing. If you do either +\tr{+RTS -Sstderr}\index{-Sstderr RTS option} or \tr{+RTS -sstderr}, +then you'll get mutator, garbage-collection, etc., times on standard +error which, for PVM programs, appears in \tr{/tmp/pvml.nnn}. + +Whether doing \tr{+RTS -Sstderr} or not, a handy way to watch +what's happening overall is: \tr{tail -f /tmp/pvml.nnn}. + +%************************************************************************ +%* * \subsubsection[parallel-rts-opts]{RTS options for Concurrent/Parallel Haskell} \index{RTS options, concurrent} \index{RTS options, parallel} |