10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /**
  25  * @test TestSmallHeap
  26  * @bug 8067438 8152239
  27  * @requires vm.gc=="null"
  28  * @summary Verify that starting the VM with a small heap works
  29  * @library /testlibrary /test/lib /test/lib/share/classes

  30  * @modules java.base/jdk.internal.misc
  31  * @modules java.management/sun.management
  32  * @build TestSmallHeap
  33  * @run main ClassFileInstaller sun.hotspot.WhiteBox
  34  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI TestSmallHeap
  35  */
  36 
  37 /* Note: It would be nice to verify the minimal supported heap size (2m) here,
  38  * but we align the heap size based on the card table size. And the card table
  39  * size is aligned based on the minimal pages size provided by the os. This
  40  * means that on most platforms, where the minimal page size is 4k, we get a
  41  * minimal heap size of 2m but on Solaris/Sparc we have a page size of 8k and
  42  * get a minimal heap size of 4m. And on platforms where the page size is 64k
  43  * we get a minimal heap size of 32m. We never use large pages for the card table.
  44  *
  45  * There is also no check in the VM for verifying that the maximum heap size
  46  * is larger than the supported minimal heap size. This means that specifying
  47  * -Xmx1m on the command line is fine but will give a heap of 2m (or 4m or 32m).
  48  *
  49  * To work around these rather strange behaviors this test uses -Xmx2m but then

  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /**
  25  * @test TestSmallHeap
  26  * @bug 8067438 8152239
  27  * @requires vm.gc=="null"
  28  * @summary Verify that starting the VM with a small heap works
  29  * @library /testlibrary /test/lib /test/lib/share/classes
  30  * @ignore 8161552
  31  * @modules java.base/jdk.internal.misc
  32  * @modules java.management/sun.management
  33  * @build TestSmallHeap
  34  * @run main ClassFileInstaller sun.hotspot.WhiteBox
  35  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI TestSmallHeap
  36  */
  37 
  38 /* Note: It would be nice to verify the minimal supported heap size (2m) here,
  39  * but we align the heap size based on the card table size. And the card table
  40  * size is aligned based on the minimal pages size provided by the os. This
  41  * means that on most platforms, where the minimal page size is 4k, we get a
  42  * minimal heap size of 2m but on Solaris/Sparc we have a page size of 8k and
  43  * get a minimal heap size of 4m. And on platforms where the page size is 64k
  44  * we get a minimal heap size of 32m. We never use large pages for the card table.
  45  *
  46  * There is also no check in the VM for verifying that the maximum heap size
  47  * is larger than the supported minimal heap size. This means that specifying
  48  * -Xmx1m on the command line is fine but will give a heap of 2m (or 4m or 32m).
  49  *
  50  * To work around these rather strange behaviors this test uses -Xmx2m but then