/* * Copyright (c) 2014, 2019, 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_GC_SHARED_STRINGDEDUP_STRINGDEDUPTHREAD_HPP #define SHARE_GC_SHARED_STRINGDEDUP_STRINGDEDUPTHREAD_HPP #include "gc/shared/concurrentGCThread.hpp" #include "gc/shared/stringdedup/stringDedupStat.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 StringDedupThread: public ConcurrentGCThread { protected: static StringDedupThread* _thread; StringDedupThread(); ~StringDedupThread(); void print_start(const StringDedupStat* last_stat); void print_end(const StringDedupStat* last_stat, const StringDedupStat* total_stat); virtual void pre_run(); virtual void post_run(); void run_service() { this->do_deduplication(); } void stop_service(); void deduplicate_shared_strings(StringDedupStat* stat); protected: virtual void do_deduplication() = 0; public: static StringDedupThread* thread(); }; template class StringDedupThreadImpl : public StringDedupThread { private: StringDedupThreadImpl() { } protected: void do_deduplication(); public: static void create(); }; #endif // SHARE_GC_SHARED_STRINGDEDUP_STRINGDEDUPTHREAD_HPP