hotspot/src/share/vm/gc_implementation/g1/g1StringDedupThread.hpp
author pliden
Tue, 18 Mar 2014 19:07:22 +0100
changeset 23472 35e93890ed88
child 24093 095cc0a63ed9
permissions -rw-r--r--
8029075: String deduplication in G1 Summary: Implementation of JEP 192, http://openjdk.java.net/jeps/192 Reviewed-by: brutisso, tschatzl, coleenp

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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.
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#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