diff src/share/vm/gc_implementation/g1/g1StringDedupThread.hpp @ 17764:595c0f60d50d

8029075: String deduplication in G1 Summary: Implementation of JEP 192, http://openjdk.java.net/jeps/192 Reviewed-by: brutisso, tschatzl, coleenp
author pliden
date Tue, 18 Mar 2014 19:07:22 +0100
parents
children 1772223a25a2
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/gc_implementation/g1/g1StringDedupThread.hpp	Tue Mar 18 19:07:22 2014 +0100
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+/*
+ * 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.
+ *
+ * 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.
+ *
+ */
+
+#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1STRINGDEDUPTHREAD_HPP
+#define SHARE_VM_GC_IMPLEMENTATION_G1_G1STRINGDEDUPTHREAD_HPP
+
+#include "gc_implementation/g1/g1StringDedupStat.hpp"
+#include "gc_implementation/shared/concurrentGCThread.hpp"
+
+//
+// The deduplication thread is where the actual deduplication occurs. It waits for
+// deduplication candidates to appear on the deduplication queue, removes them from
+// the queue and tries to deduplicate them. It uses the deduplication hashtable to
+// find identical, already existing, character arrays on the heap. The thread runs
+// concurrently with the Java application but participates in safepoints to allow
+// the GC to adjust and unlink oops from the deduplication queue and table.
+//
+class G1StringDedupThread: public ConcurrentGCThread {
+private:
+  static G1StringDedupThread* _thread;
+
+  G1StringDedupThread();
+  ~G1StringDedupThread();
+
+  void print(outputStream* st, const G1StringDedupStat& last_stat, const G1StringDedupStat& total_stat);
+
+public:
+  static void create();
+  static G1StringDedupThread* thread();
+
+  virtual void run();
+  virtual void print_on(outputStream* st) const;
+};
+
+#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1STRINGDEDUPTHREAD_HPP