- move from AlphaThorns

git-svn-id: http://svn.cactuscode.org/arrangements/CactusUtils/Nice/trunk@2 ca4eca94-0e4f-0410-9877-d0c6952cf786

9 files changed, 593 insertions, 0 deletions

diff --git a/COPYING b/COPYING
new file mode 100644
index 0000000..5b6e7c6
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,340 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+                       59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
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+License is intended to guarantee your freedom to share and change free
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+Foundation's software and to any other program whose authors commit to
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+
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+		     END OF TERMS AND CONDITIONS
+
+	    How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
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+    <one line to give the program's name and a brief idea of what it does.>
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+    This program is free software; you can redistribute it and/or modify
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+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
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+    You should have received a copy of the GNU General Public License
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+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
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+Also add information on how to contact you by electronic and paper mail.
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+    This is free software, and you are welcome to redistribute it
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+The hypothetical commands `show w' and `show c' should show the appropriate
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+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
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+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/README b/README
new file mode 100644
index 0000000..bd574ca
--- /dev/null
+++ b/README
@@ -0,0 +1,31 @@
+Purpose of this thorn
+---------------------
+This thorn changes the nice level of Cactus processes.
+
+
+Documentation
+-------------
+Look into the doc/ directory for more documentation.
+
+
+Copyright
+---------
+
+This thorn is copyright (C) 2002
+by Frank Loeffler <frank.loeffler@aei.mpg.de>
+
+This thorn is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This thorn is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this thorn (see the file COPYING in this directory);
+if not, write to the Free Software Foundation, Inc., 59 Temple
+Place, Suite 330, Boston, MA  02111-1307  USA
+
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}
diff --git a/interface.ccl b/interface.ccl
new file mode 100644
index 0000000..4f6ea6e
--- /dev/null
+++ b/interface.ccl
@@ -0,0 +1,4 @@
+# Interface definition for thorn Nice
+
+implements: nice
+
diff --git a/param.ccl b/param.ccl
new file mode 100644
index 0000000..1179281
--- /dev/null
+++ b/param.ccl
@@ -0,0 +1,7 @@
+# Parameter definitions for thorn Nice
+
+CCTK_INT Nice_nice "Nice level"
+{
+-20:19 :: "The range for the nice is from -20 to 19, but only root can use negative values, default is 19."
+} 19
+
diff --git a/schedule.ccl b/schedule.ccl
new file mode 100644
index 0000000..6a5ef00
--- /dev/null
+++ b/schedule.ccl
@@ -0,0 +1,6 @@
+# Schedule definitions for thorn Nice
+schedule Nice_Renice at CCTK_STARTUP
+{
+    LANG: C
+}   "Renice the process"
+
diff --git a/src/make.code.defn b/src/make.code.defn
new file mode 100644
index 0000000..1fa5f0a
--- /dev/null
+++ b/src/make.code.defn
@@ -0,0 +1,3 @@
+# Main make.code.defn file for thorn Nice
+# Source files in this directory
+SRCS = nice.c
diff --git a/src/nice.c b/src/nice.c
new file mode 100644
index 0000000..1036ad1
--- /dev/null
+++ b/src/nice.c
@@ -0,0 +1,147 @@
+#include "cctk.h"
+#include "cctk_WarnLevel.h"
+#include "cctk_Arguments.h"
+#include "cctk_Parameters.h"
+
+/* manpage of getpriority:
+   Including  <sys/time.h>  is  not  required  these days,
+   but increases portability.
+*/
+#include <sys/time.h>
+#include <errno.h>
+#include <sys/resource.h>
+
+void Nice_Renice(CCTK_ARGUMENTS)
+{
+    /* do not declare the arguments, it will cause an error */
+    DECLARE_CCTK_PARAMETERS
+
+    int old_nice, new_nice, nice_return_value;
+
+    /* reset error variable */
+    errno=0;
+    /* save the old nice value */
+    old_nice=getpriority(PRIO_PROCESS, 0);
+    /* check errno */
+    if (errno)
+    {
+        switch (errno)
+        {
+          case ESRCH  : /* this should never occur, since the 0 in getpriority
+                           means this process, which should be found
+                        */
+                        CCTK_INFO("getpriority received ESTCH-error.");
+                        break;
+          case EINVAL : /* this should definitly not occur */
+                        CCTK_INFO("getpriority received EINVAL-error.");
+                        break;
+          case EPERM  : /* this should never occur
+                           It means, that the user of process did not match the
+                           callers user */
+                        CCTK_INFO("getpriority received EPERM-error.");
+                        break;
+          case EACCES : /* This cannot occur: non root user attemted to lower
+                           priority (since we did not call setpriority here */
+                        CCTK_INFO("getpriority received EACCES-error.");
+                        break;
+          default:      /* This should not occur, otherwise it is an
+                           undocumented errno */
+                        CCTK_VInfo(CCTK_THORNSTRING,
+                                   "getpriority got undocumented errno %d",
+                                   errno);
+        }
+        CCTK_WARN(0, "This should never occur.");
+        /* in case CCTK_WARN did not stop the code */
+        CCTK_Abort(cctkGH, 1);
+    }
+
+    errno=0;
+    /* try to set the new priority */
+    nice_return_value=setpriority(PRIO_PROCESS, 0, Nice_nice);
+    /* check return value */
+    if (nice_return_value!=0)
+    {
+        switch (errno)
+        {
+          case ESRCH  : /* this should never occur, since the 0 in setpriority
+                           means this process, which should be found
+                        */
+                        CCTK_INFO("setpriority received ESTCH-error.");
+                        CCTK_WARN(0, "This should never occur.");
+                        break;
+          case EINVAL : /* this should definitly not occur */
+                        CCTK_INFO("setpriority received EINVAL-error.");
+                        CCTK_WARN(0, "This should never occur.");
+                        break;
+          case EPERM  : /* this should never occur
+                           It means, that the user of process did not match the
+                           callers user */
+                        CCTK_INFO("setpriority received EPERM-error.");
+                        CCTK_WARN(0, "This should never occur.");
+                        break;
+          case EACCES : /* This can occur: non root user attemted to lower
+                           priority
+                        */
+                        CCTK_WARN(0, "Only root can lower priorities.");
+                        break;
+          default:      /* This should not occur, otherwise it is an
+                           undocumented errno */
+                        CCTK_VInfo(CCTK_THORNSTRING,
+                                   "setpriority got undocumented errno %d",
+                                   errno);
+        }
+        /* in case CCTK_WARN did not stop the code */
+        CCTK_Abort(cctkGH, 1);
+    }
+
+    errno=0;
+    /* It should ok, but check the new priority */
+    new_nice=getpriority(PRIO_PROCESS, 0);
+    /* check errno */
+    if (errno)
+    {
+        switch (errno)
+        {
+          case ESRCH  : /* this should never occur, since the 0 in getpriority
+                           means this process, which should be found */
+                        CCTK_INFO("getpriority received ESTCH-error.");
+                        break;
+          case EINVAL : /* this should definitly not occur */
+                        CCTK_INFO("getpriority received EINVAL-error.");
+                        break;
+          case EPERM  : /* this should never occur
+                           It means, that the user of process did not match the
+                           callers user */
+                        CCTK_INFO("getpriority received EPERM-error.");
+                        break;
+          case EACCES : /* This cannot occur: non root user attemted to lower
+                           priority (since we did not call setpriority here
+                        */
+                        CCTK_INFO("getpriority received EACCES-error.");
+                        break;
+          default:      /* This should not occur, otherwise it is an
+                           undocumented errno */
+                        CCTK_VInfo(CCTK_THORNSTRING,
+                                   "getpriority got undocumented errno %d",
+                                   errno);
+        }
+        CCTK_WARN(0, "This should never occur.");
+        /* in case CCTK_WARN did not stop the code */
+        CCTK_Abort(cctkGH, 1);
+    }
+
+    if (new_nice == Nice_nice)
+    {
+        CCTK_VInfo(CCTK_THORNSTRING,"Process reniced from nice level %d to %d.",
+                                    old_nice, new_nice);
+    }
+    else
+    {
+        /* this should never occur because of the error handling before */
+        CCTK_VInfo(CCTK_THORNSTRING,
+                   "Process reniced to nice level %d instead of %d.",
+                   new_nice, Nice_nice);
+    }
+
+}
+
diff --git a/test/nice.par b/test/nice.par
new file mode 100644
index 0000000..0f4b964
--- /dev/null
+++ b/test/nice.par
@@ -0,0 +1 @@
+ActiveThorns = "nice"