1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/gc_implementation/shared/gcOverheadReporter.hpp Thu Jun 05 15:57:56 2008 -0700
1.3 @@ -0,0 +1,141 @@
1.4 +/*
1.5 + * Copyright 2001-2007 Sun Microsystems, Inc. All Rights Reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
1.23 + * CA 95054 USA or visit www.sun.com if you need additional information or
1.24 + * have any questions.
1.25 + *
1.26 + */
1.27 +
1.28 +// Keeps track of the GC overhead (both concurrent and STW). It stores
1.29 +// it in a large array and then prints it to tty at the end of the
1.30 +// execution.
1.31 +
1.32 +// See coTracker.hpp for the explanation on what groups are.
1.33 +
1.34 +// Let's set a maximum number of concurrent overhead groups, to
1.35 +// statically allocate any arrays we need and not to have to
1.36 +// malloc/free them. This is just a bit more convenient.
1.37 +enum {
1.38 + MaxGCOverheadGroupNum = 4
1.39 +};
1.40 +
1.41 +typedef struct {
1.42 + double _start_sec;
1.43 + double _end_sec;
1.44 +
1.45 + double _conc_overhead[MaxGCOverheadGroupNum];
1.46 + double _stw_overhead;
1.47 +} GCOverheadReporterEntry;
1.48 +
1.49 +class GCOverheadReporter {
1.50 + friend class COReportingThread;
1.51 +
1.52 +private:
1.53 + enum PrivateConstants {
1.54 + DefaultReporterLength = 128 * 1024
1.55 + };
1.56 +
1.57 + // Reference to the single instance of this class.
1.58 + static GCOverheadReporter* _reporter;
1.59 +
1.60 + // These three references point to the array that contains the GC
1.61 + // overhead entries (_base is the base of the array, _top is the
1.62 + // address passed the last entry of the array, _curr is the next
1.63 + // entry to be used).
1.64 + GCOverheadReporterEntry* _base;
1.65 + GCOverheadReporterEntry* _top;
1.66 + GCOverheadReporterEntry* _curr;
1.67 +
1.68 + // The number of concurrent overhead groups.
1.69 + size_t _group_num;
1.70 +
1.71 + // The wall-clock time of the end of the last recorded period of GC
1.72 + // overhead.
1.73 + double _prev_end_sec;
1.74 +
1.75 + // Names for the concurrent overhead groups.
1.76 + const char* _group_names[MaxGCOverheadGroupNum];
1.77 +
1.78 + // Add a new entry to the large array. conc_overhead being NULL is
1.79 + // equivalent to an array full of 0.0s. conc_overhead should have a
1.80 + // length of at least _group_num.
1.81 + void add(double start_sec, double end_sec,
1.82 + double* conc_overhead,
1.83 + double stw_overhead);
1.84 +
1.85 + // Add an entry that represents concurrent GC overhead.
1.86 + // conc_overhead must be at least of length _group_num.
1.87 + // conc_overhead being NULL is equivalent to an array full of 0.0s.
1.88 + void add_conc_overhead(double start_sec, double end_sec,
1.89 + double* conc_overhead) {
1.90 + add(start_sec, end_sec, conc_overhead, 0.0);
1.91 + }
1.92 +
1.93 + // Add an entry that represents STW GC overhead.
1.94 + void add_stw_overhead(double start_sec, double end_sec,
1.95 + double stw_overhead) {
1.96 + add(start_sec, end_sec, NULL, stw_overhead);
1.97 + }
1.98 +
1.99 + // It records the start of a STW pause (i.e. it records the
1.100 + // concurrent overhead up to that point)
1.101 + void record_stw_start(double start_sec);
1.102 +
1.103 + // It records the end of a STW pause (i.e. it records the overhead
1.104 + // associated with the pause and adjusts all the trackers to reflect
1.105 + // the pause)
1.106 + void record_stw_end(double end_sec);
1.107 +
1.108 + // It queries all the trackers of their concurrent overhead and
1.109 + // records it.
1.110 + void collect_and_record_conc_overhead(double end_sec);
1.111 +
1.112 + // It prints the contents of the GC overhead array
1.113 + void print() const;
1.114 +
1.115 +
1.116 + // Constructor. The same preconditions for group_num and group_names
1.117 + // from initGCOverheadReporter apply here too.
1.118 + GCOverheadReporter(size_t group_num,
1.119 + const char* group_names[],
1.120 + size_t length = DefaultReporterLength);
1.121 +
1.122 +public:
1.123 +
1.124 + // statics
1.125 +
1.126 + // It initialises the GCOverheadReporter and launches the concurrent
1.127 + // overhead reporting thread. Both actions happen only if the
1.128 + // GCOverheadReporting parameter is set. The length of the
1.129 + // group_names array should be >= group_num and group_num should be
1.130 + // <= MaxGCOverheadGroupNum. Entries group_namnes[0..group_num-1]
1.131 + // should not be NULL.
1.132 + static void initGCOverheadReporter(size_t group_num,
1.133 + const char* group_names[]);
1.134 +
1.135 + // The following three are provided for convenience and they are
1.136 + // wrappers around record_stw_start(start_sec), record_stw_end(end_sec),
1.137 + // and print(). Each of these checks whether GC overhead reporting
1.138 + // is on (i.e. _reporter != NULL) and, if it is, calls the
1.139 + // corresponding method. Saves from repeating this pattern again and
1.140 + // again from the places where they need to be called.
1.141 + static void recordSTWStart(double start_sec);
1.142 + static void recordSTWEnd(double end_sec);
1.143 + static void printGCOverhead();
1.144 +};
