ctest: Optionally avoid starting tests that may exceed a given CPU load

Add a TestLoad setting to CTest that can be set via a new --test-load
command-line option, CTEST_TEST_LOAD variable, or TEST_LOAD option to
the ctest_test command.  Teach cmCTestMultiProcessHandler to measure
the CPU load and avoid starting tests that may take more than the
spare load currently available.  The expression

 <current_load> + <test_processors> <= <max-load>

must be true to start a new test.

Co-Author: Zack Galbreath <zack.galbreath@kitware.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/Source/CTest/cmCTestGenericHandler.h b/Source/CTest/cmCTestGenericHandler.h
index 8567dd7..4b7ae79 100644
--- a/Source/CTest/cmCTestGenericHandler.h
+++ b/Source/CTest/cmCTestGenericHandler.h
@@ -89,6 +89,8 @@ public:
   void SetAppendXML(bool b) { this->AppendXML = b; }
   void SetQuiet(bool b) { this->Quiet = b; }
   bool GetQuiet() { return this->Quiet; }
+  void SetTestLoad(unsigned long load) { this->TestLoad = load; }
+  unsigned long GetTestLoad() const { return this->TestLoad;  }
 
 protected:
   bool StartResultingXML(cmCTest::Part part,
@@ -97,6 +99,7 @@ protected:
 
   bool AppendXML;
   bool Quiet;
+  unsigned long TestLoad;
   cmSystemTools::OutputOption HandlerVerbose;
   cmCTest *CTest;
   t_StringToString Options;