From de060c4f15ee62ac074d6fad2b66426673a49398 Mon Sep 17 00:00:00 2001 From: knarf Date: Fri, 20 Feb 2004 14:26:34 +0000 Subject: - move from AlphaThorns git-svn-id: http://svn.cactuscode.org/arrangements/CactusUtils/Nice/trunk@2 ca4eca94-0e4f-0410-9877-d0c6952cf786 --- doc/documentation.tex | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 doc/documentation.tex (limited to 'doc/documentation.tex') diff --git a/doc/documentation.tex b/doc/documentation.tex new file mode 100644 index 0000000..901f08b --- /dev/null +++ b/doc/documentation.tex @@ -0,0 +1,54 @@ +\documentclass{article} + +% Use the Cactus ThornGuide style file +% (Automatically used from Cactus distribution, if you have a +% thorn without the Cactus Flesh download this from the Cactus +% homepage at www.cactuscode.org) +\usepackage{../../../../doc/ThornGuide/cactus} + +\begin{document} + +\title{Nice} +\author{Frank L\"offler (knarf@aei.mpg.de)} +\date{$ $Date$ $} + +\maketitle + +% Do not delete next line +% START CACTUS THORNGUIDE + +\begin{abstract} +Simple tool for using a (configurable) nice level for all processes. +\end{abstract} + +\section{Comments} + +This thorn tries to renice all processes of Cactus to a given nice level.\\ +To renice a process means to change its nice level after the start. The nice +level is a way to control the priority of processes for cpu power. It is +always a good idea to give cpu-intensive jobs (like Cactus runs) a low +priority if you are using desktop machines, especially if other people are +using them too. + +The nice level has a range of $-20$ to $19$. A higher number means less +priority. Mostly, normal processes will get $0$ and only the superuser +(root) can use negative values. Also only root can lower the nice level +of a process, so if you nice your Cactus Run to 19, you cannot renice it +later to an lower nice-level. The nice level of single +processes can be controled by the system commands $nice$ and/or $renice$. +In the case of Cactus and Lamd this is not possible at startup. Therefore +this thorn will set the nice level of your processes at CCTK\_PARAMCHECK +(in the beginning of the calculation).\\ +This thorn has only one parameter: +\begin{verbatim} + CCTK_INT Nice_nice +\end{verbatim} +which is by default 19.\\*[1cm] +Note to developers:\\ +This thorn uses $getpriority()$ and $setpriority()$ and therefore needs +the includes $<$sys/time.h$>$, $<$errno.h$>$ and $<$sys/resource.h$>$. +If these are not provided on some platform, please tell me. +% Do not delete next line +% END CACTUS THORNGUIDE + +\end{document} -- cgit v1.2.3