test/runtime/os/AvailableProcessors.java

@@ -25,11 +25,11 @@
 import jdk.test.lib.OutputAnalyzer;
 import java.util.ArrayList;
 
 /*
  * @test
- * @bug 6515172
+ * @bug 6515172 8148766
  * @summary Check that availableProcessors reports the correct value when running in a cpuset on linux
  * @requires os.family == "linux"
  * @library /testlibrary
  * @build jdk.test.lib.*
  * @run driver AvailableProcessors

@@ -91,11 +91,13 @@
         }
     }
 
     static void checkProcessors(int expected) {
         int available = Runtime.getRuntime().availableProcessors();
-        if (available != expected)
+        // available can dynamically drop below expected due to aggressive power management
+        // but we should never have more than expected, else taskset is broken
+        if (available > expected)
             throw new Error("Expected " + expected + " processors, but found "
                             + available);
         else
             System.out.println(SUCCESS_STRING + available);
     }