test/gc/TestSmallHeap.java

rev 7621 : [mq]: smalltest

*** 1,7 ****
  /*
!  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
--- 1,7 ----
  /*
!  * Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
*** 24,59 ****
  /**
   * @test TestSmallHeap
   * @bug 8067438
   * @requires vm.gc=="null"
   * @summary Verify that starting the VM with a small heap works
!  * @library /testlibrary
!  * @run main/othervm -Xmx4m -XX:+UseParallelGC TestSmallHeap
!  * @run main/othervm -Xmx4m -XX:+UseSerialGC TestSmallHeap
!  * @run main/othervm -Xmx4m -XX:+UseG1GC TestSmallHeap
!  * @run main/othervm -Xmx4m -XX:+UseConcMarkSweepGC -XX:CMSMarkStackSizeMax=1032 TestSmallHeap
!  *
!  * Note: It would be nice to verify the minimal supported heap size here,
!  * but that turns out to be quite tricky since we align the heap size based
!  * on the card table size. And the card table size is aligned based on the
!  * minimal pages size provided by the os. This means that on most platforms,
!  * where the minimal page size is 4k, we get a minimal heap size of 2m but
!  * on Solaris/Sparc we have a page size of 8k and get a minimal heap size
!  * of 8m.
   * There is also no check in the VM for verifying that the maximum heap size
   * is larger than the supported minimal heap size. This means that specifying
!  * -Xmx1m on the command line is fine but will give a heap of 2m (or 4m).
!  * To work around these rather strange behaviors this test uses 4m for all
!  * platforms.
   */
  
! import sun.management.ManagementFactoryHelper;
  import static com.oracle.java.testlibrary.Asserts.*;
  
  public class TestSmallHeap {
  
      public static void main(String[] args) {
          String maxHeap = ManagementFactoryHelper.getDiagnosticMXBean().getVMOption("MaxHeapSize").getValue();
!         String expectedMaxHeap = "4194304";
!         assertEQ(maxHeap, expectedMaxHeap);
      }
  }
--- 24,71 ----
  /**
   * @test TestSmallHeap
   * @bug 8067438
   * @requires vm.gc=="null"
   * @summary Verify that starting the VM with a small heap works
!  * @library /testlibrary /../../test/lib
!  * @build TestSmallHeap
!  * @run main ClassFileInstaller sun.hotspot.WhiteBox
!  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xmx2m -XX:+UseParallelGC TestSmallHeap
!  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xmx2m -XX:+UseSerialGC TestSmallHeap
!  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xmx2m -XX:+UseG1GC TestSmallHeap
!  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xmx2m -XX:+UseConcMarkSweepGC TestSmallHeap
!  *
!  * Note: It would be nice to verify the minimal supported heap size (2m) here,
!  * but we align the heap size based on the card table size. And the card table
!  * size is aligned based on the minimal pages size provided by the os. This
!  * means that on most platforms, where the minimal page size is 4k, we get a
!  * minimal heap size of 2m but on Solaris/Sparc we have a page size of 8k and
!  * get a minimal heap size of 4m. And on platforms where the page size is 64k
!  * we get a minimal heap size of 32m. We never use large pages for the card table.
!  *
   * There is also no check in the VM for verifying that the maximum heap size
   * is larger than the supported minimal heap size. This means that specifying
!  * -Xmx1m on the command line is fine but will give a heap of 2m (or 4m or 32m).
!  * 
!  * To work around these rather strange behaviors this test uses -Xmx2m but then
!  * calculates what the expected heap size should be. The calculation is a
!  * simplified version of the code in the VM. We assume that the card table will
!  * use one page. Each byte in the card table corresponds to 512 bytes on the heap.
!  * So, the expected heap size is page_size * 512.
   */
  
! import com.oracle.java.testlibrary.*;
  import static com.oracle.java.testlibrary.Asserts.*;
+ import sun.hotspot.WhiteBox;
+ import sun.management.ManagementFactoryHelper;
  
  public class TestSmallHeap {
  
      public static void main(String[] args) {
+         WhiteBox wb = WhiteBox.getWhiteBox();
+         int pageSize = wb.getVMPageSize();
+         int heapBytesPerCard = 512;
+         long expectedMaxHeap = pageSize * heapBytesPerCard;
          String maxHeap = ManagementFactoryHelper.getDiagnosticMXBean().getVMOption("MaxHeapSize").getValue();
!         assertEQ(Long.parseLong(maxHeap), expectedMaxHeap);
      }
  }