--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc/shared/ageTable.cpp	Wed May 13 15:16:06 2015 +0200
@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 1997, 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.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc/shared/ageTable.hpp"
+#include "gc/shared/collectedHeap.hpp"
+#include "gc/shared/collectorPolicy.hpp"
+#include "gc/shared/gcPolicyCounters.hpp"
+#include "memory/resourceArea.hpp"
+#include "runtime/atomic.inline.hpp"
+#include "utilities/copy.hpp"
+
+/* Copyright (c) 1992, 2015, Oracle and/or its affiliates, and Stanford University.
+   See the LICENSE file for license information. */
+
+ageTable::ageTable(bool global) {
+
+  clear();
+
+  if (UsePerfData && global) {
+
+    ResourceMark rm;
+    EXCEPTION_MARK;
+
+    const char* agetable_ns = "generation.0.agetable";
+    const char* bytes_ns = PerfDataManager::name_space(agetable_ns, "bytes");
+
+    for(int age = 0; age < table_size; age ++) {
+      char age_name[10];
+      jio_snprintf(age_name, sizeof(age_name), "%2.2d", age);
+      const char* cname = PerfDataManager::counter_name(bytes_ns, age_name);
+      _perf_sizes[age] = PerfDataManager::create_variable(SUN_GC, cname,
+                                                          PerfData::U_Bytes,
+                                                          CHECK);
+    }
+
+    const char* cname = PerfDataManager::counter_name(agetable_ns, "size");
+    PerfDataManager::create_constant(SUN_GC, cname, PerfData::U_None,
+                                     table_size, CHECK);
+  }
+}
+
+void ageTable::clear() {
+  for (size_t* p = sizes; p < sizes + table_size; ++p) {
+    *p = 0;
+  }
+}
+
+void ageTable::merge(ageTable* subTable) {
+  for (int i = 0; i < table_size; i++) {
+    sizes[i]+= subTable->sizes[i];
+  }
+}
+
+void ageTable::merge_par(ageTable* subTable) {
+  for (int i = 0; i < table_size; i++) {
+    Atomic::add_ptr(subTable->sizes[i], &sizes[i]);
+  }
+}
+
+uint ageTable::compute_tenuring_threshold(size_t survivor_capacity, GCPolicyCounters* gc_counters) {
+  size_t desired_survivor_size = (size_t)((((double) survivor_capacity)*TargetSurvivorRatio)/100);
+  uint result;
+
+  if (AlwaysTenure || NeverTenure) {
+    assert(MaxTenuringThreshold == 0 || MaxTenuringThreshold == markOopDesc::max_age + 1,
+        err_msg("MaxTenuringThreshold should be 0 or markOopDesc::max_age + 1, but is " UINTX_FORMAT, MaxTenuringThreshold));
+    result = MaxTenuringThreshold;
+  } else {
+    size_t total = 0;
+    uint age = 1;
+    assert(sizes[0] == 0, "no objects with age zero should be recorded");
+    while (age < table_size) {
+      total += sizes[age];
+      // check if including objects of age 'age' made us pass the desired
+      // size, if so 'age' is the new threshold
+      if (total > desired_survivor_size) break;
+      age++;
+    }
+    result = age < MaxTenuringThreshold ? age : MaxTenuringThreshold;
+  }
+
+  if (PrintTenuringDistribution || UsePerfData) {
+
+    if (PrintTenuringDistribution) {
+      gclog_or_tty->cr();
+      gclog_or_tty->print_cr("Desired survivor size " SIZE_FORMAT " bytes, new threshold "
+        UINTX_FORMAT " (max threshold " UINTX_FORMAT ")",
+        desired_survivor_size*oopSize, (uintx) result, MaxTenuringThreshold);
+    }
+
+    size_t total = 0;
+    uint age = 1;
+    while (age < table_size) {
+      total += sizes[age];
+      if (sizes[age] > 0) {
+        if (PrintTenuringDistribution) {
+          gclog_or_tty->print_cr("- age %3u: " SIZE_FORMAT_W(10) " bytes, " SIZE_FORMAT_W(10) " total",
+                                        age,    sizes[age]*oopSize,          total*oopSize);
+        }
+      }
+      if (UsePerfData) {
+        _perf_sizes[age]->set_value(sizes[age]*oopSize);
+      }
+      age++;
+    }
+    if (UsePerfData) {
+      gc_counters->tenuring_threshold()->set_value(result);
+      gc_counters->desired_survivor_size()->set_value(
+        desired_survivor_size*oopSize);
+    }
+  }
+
+  return result;
+}