From 5592e89cfa8d99081abe1e00c5e3baeb2a4a4e72 Mon Sep 17 00:00:00 2001
From: Ralf Hartmann <Ralf.Hartmann@dlr.de>
Date: Fri, 25 Aug 2000 12:01:26 +0000
Subject: [PATCH] use of getrusage with RUSAGE_CHILDREN, but still the Timer
 class does not work in multithreading (at least not on Solaris7).

git-svn-id: https://svn.dealii.org/trunk@3270 0785d39b-7218-0410-832d-ea1e28bc413d
---
 deal.II/base/include/base/timer.h | 23 +++++++++++++++++++++++
 deal.II/base/source/timer.cc      | 17 ++++++++++++++++-
 deal.II/doc/news/2000/c-3-0.html  | 11 +++++++++++
 3 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/deal.II/base/include/base/timer.h b/deal.II/base/include/base/timer.h
index 2e9691d37f..2d99107a12 100644
--- a/deal.II/base/include/base/timer.h
+++ b/deal.II/base/include/base/timer.h
@@ -96,6 +96,29 @@ class Timer
 				      */
     double              start_time;
 
+
+				     /**
+				      * Similar to @p{start_time}, but
+				      * needed for children threads
+				      * in multithread mode. Value of
+				      * the user time when @p{start}
+				      * was called the last time or
+				      * when the object was created
+				      * and no @p{stop} was issued in
+				      * between.
+				      *
+				      * For some reason (error in
+				      * operating system?) the
+				      * function call
+				      * @p{getrusage(RUSAGE_CHILDREN,.)}
+				      * gives always 0 (at least
+				      * on Solaris7). Hence the
+				      * @p{Timer} class still does not
+				      * yet work for multithreading
+				      * mode.
+				      */
+    double              start_time_children;
+
 				     /**
 				      * Accumulated time for all previous
 				      * @p{start}/@p{stop} cycles. The time for
diff --git a/deal.II/base/source/timer.cc b/deal.II/base/source/timer.cc
index 25e93882ca..79fc37c8ab 100644
--- a/deal.II/base/source/timer.cc
+++ b/deal.II/base/source/timer.cc
@@ -46,6 +46,10 @@ void Timer::start ()
   rusage usage;
   getrusage (RUSAGE_SELF, &usage);
   start_time = usage.ru_utime.tv_sec + 1.e-6 * usage.ru_utime.tv_usec;
+
+  rusage usage_children;
+  getrusage (RUSAGE_CHILDREN, &usage_children);
+  start_time_children = usage_children.ru_utime.tv_sec + 1.e-6 * usage_children.ru_utime.tv_usec;
 }
 
 
@@ -59,6 +63,12 @@ double Timer::stop ()
       getrusage (RUSAGE_SELF, &usage);
       const double dtime = usage.ru_utime.tv_sec + 1.e-6 * usage.ru_utime.tv_usec;
       cumulative_time += dtime - start_time;
+
+      rusage usage_children;
+      getrusage (RUSAGE_CHILDREN, &usage_children);
+      const double dtime_children =
+	usage_children.ru_utime.tv_sec + 1.e-6 * usage_children.ru_utime.tv_usec;
+      cumulative_time += dtime_children - start_time_children;
     }
   return cumulative_time;
 }
@@ -72,8 +82,13 @@ double Timer::operator() () const
       rusage usage;
       getrusage (RUSAGE_SELF, &usage);
       const double dtime =  usage.ru_utime.tv_sec + 1.e-6 * usage.ru_utime.tv_usec;
+      
+      rusage usage_children;
+      getrusage (RUSAGE_CHILDREN, &usage_children);
+      const double dtime_children =
+	usage_children.ru_utime.tv_sec + 1.e-6 * usage_children.ru_utime.tv_usec;
 
-      return dtime - start_time + cumulative_time;
+      return dtime - start_time + dtime_children - start_time_children + cumulative_time;
     }
   else
     return cumulative_time;
diff --git a/deal.II/doc/news/2000/c-3-0.html b/deal.II/doc/news/2000/c-3-0.html
index 4092d480aa..cdca5f3198 100644
--- a/deal.II/doc/news/2000/c-3-0.html
+++ b/deal.II/doc/news/2000/c-3-0.html
@@ -106,6 +106,17 @@
 <h3>base</h3>
 
 <ol>
+  <li> <p> 
+       New: <code class="class">Timer</code> now uses the system
+       function <code class="member">getrusage (RUSAGE_CHILDREN,
+       .)</code> that is need in multithreading. But still the <code
+       class="class">Timer</code> class does not yet work in
+       multithreading, as getrusage with flag RUSAGE_CHILDREN gives always
+       0 (at least on Solaris7).
+       <br>
+       (Ralf Hartmann 2000/08/25)
+       </p>   
+
   <li> <p>
        New: There are now a set of functions
        <code class="member">outer_product</code> that for the outer
-- 
2.39.5