6711316: Open source the Garbage-First garbage collector

First mercurial integration of the code for the Garbage-First garbage collector.

Reviewed-by: apetrusenko, iveresov, jmasa, sgoldman, tonyp, ysr

hotspot/src/share/vm/gc_implementation/g1/survRateGroup.cpp

@@ -0,0 +1,264 @@
+/*
+ * Copyright 2001-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+#include "incls/_precompiled.incl"
+#include "incls/_survRateGroup.cpp.incl"
+
+SurvRateGroup::SurvRateGroup(G1CollectorPolicy* g1p,
+                             const char* name,
+                             size_t summary_surv_rates_len) :
+    _g1p(g1p), _name(name),
+    _all_regions_allocated(0),
+    _curr_length(0), _scan_only_prefix(0), _setup_seq_num(0),
+    _array_length(0), _surv_rate(NULL), _accum_surv_rate_pred(NULL),
+    _accum_surv_rate(0.0), _surv_rate_pred(NULL), _last_pred(0.0),
+    _summary_surv_rates_len(summary_surv_rates_len),
+    _summary_surv_rates_max_len(0),
+    _summary_surv_rates(NULL) {
+
+  // the following will set up the arrays with length 1
+  _curr_length = 1;
+  stop_adding_regions();
+  guarantee( _array_length == 1, "invariant" );
+  guarantee( _surv_rate_pred[0] != NULL, "invariant" );
+  _surv_rate_pred[0]->add(0.4);
+  all_surviving_words_recorded(false);
+  _curr_length = 0;
+
+  if (summary_surv_rates_len > 0) {
+    size_t length = summary_surv_rates_len;
+      _summary_surv_rates = NEW_C_HEAP_ARRAY(NumberSeq*, length);
+    if (_summary_surv_rates == NULL) {
+      vm_exit_out_of_memory(sizeof(NumberSeq*) * length,
+                            "Not enough space for surv rate summary");
+    }
+    for (size_t i = 0; i < length; ++i)
+      _summary_surv_rates[i] = new NumberSeq();
+  }
+
+  start_adding_regions();
+}
+
+void
+SurvRateGroup::start_adding_regions() {
+  _setup_seq_num   = _array_length;
+  _curr_length     = _scan_only_prefix;
+  _accum_surv_rate = 0.0;
+
+#if 0
+  gclog_or_tty->print_cr("start adding regions, seq num %d, length %d",
+                         _setup_seq_num, _curr_length);
+#endif // 0
+}
+
+void
+SurvRateGroup::stop_adding_regions() {
+  size_t length = _curr_length;
+
+#if 0
+  gclog_or_tty->print_cr("stop adding regions, length %d", length);
+#endif // 0
+
+  if (length > _array_length) {
+    double* old_surv_rate = _surv_rate;
+    double* old_accum_surv_rate_pred = _accum_surv_rate_pred;
+    TruncatedSeq** old_surv_rate_pred = _surv_rate_pred;
+
+    _surv_rate = NEW_C_HEAP_ARRAY(double, length);
+    if (_surv_rate == NULL) {
+      vm_exit_out_of_memory(sizeof(double) * length,
+                            "Not enough space for surv rate array.");
+    }
+    _accum_surv_rate_pred = NEW_C_HEAP_ARRAY(double, length);
+    if (_accum_surv_rate_pred == NULL) {
+      vm_exit_out_of_memory(sizeof(double) * length,
+                         "Not enough space for accum surv rate pred array.");
+    }
+    _surv_rate_pred = NEW_C_HEAP_ARRAY(TruncatedSeq*, length);
+    if (_surv_rate == NULL) {
+      vm_exit_out_of_memory(sizeof(TruncatedSeq*) * length,
+                            "Not enough space for surv rate pred array.");
+    }
+
+    for (size_t i = 0; i < _array_length; ++i)
+      _surv_rate_pred[i] = old_surv_rate_pred[i];
+
+#if 0
+    gclog_or_tty->print_cr("stop adding regions, new seqs %d to %d",
+                  _array_length, length - 1);
+#endif // 0
+
+    for (size_t i = _array_length; i < length; ++i) {
+      _surv_rate_pred[i] = new TruncatedSeq(10);
+      // _surv_rate_pred[i]->add(last_pred);
+    }
+
+    _array_length = length;
+
+    if (old_surv_rate != NULL)
+      FREE_C_HEAP_ARRAY(double, old_surv_rate);
+    if (old_accum_surv_rate_pred != NULL)
+      FREE_C_HEAP_ARRAY(double, old_accum_surv_rate_pred);
+    if (old_surv_rate_pred != NULL)
+      FREE_C_HEAP_ARRAY(NumberSeq*, old_surv_rate_pred);
+  }
+
+  for (size_t i = 0; i < _array_length; ++i)
+    _surv_rate[i] = 0.0;
+}
+
+double
+SurvRateGroup::accum_surv_rate(size_t adjustment) {
+  // we might relax this one in the future...
+  guarantee( adjustment == 0 || adjustment == 1, "pre-condition" );
+
+  double ret = _accum_surv_rate;
+  if (adjustment > 0) {
+    TruncatedSeq* seq = get_seq(_curr_length+1);
+    double surv_rate = _g1p->get_new_prediction(seq);
+    ret += surv_rate;
+  }
+
+  return ret;
+}
+
+int
+SurvRateGroup::next_age_index() {
+  TruncatedSeq* seq = get_seq(_curr_length);
+  double surv_rate = _g1p->get_new_prediction(seq);
+  _accum_surv_rate += surv_rate;
+
+  ++_curr_length;
+  return (int) ++_all_regions_allocated;
+}
+
+void
+SurvRateGroup::record_scan_only_prefix(size_t scan_only_prefix) {
+  guarantee( scan_only_prefix <= _curr_length, "pre-condition" );
+  _scan_only_prefix = scan_only_prefix;
+}
+
+void
+SurvRateGroup::record_surviving_words(int age_in_group, size_t surv_words) {
+  guarantee( 0 <= age_in_group && (size_t) age_in_group < _curr_length,
+             "pre-condition" );
+  guarantee( _surv_rate[age_in_group] <= 0.00001,
+             "should only update each slot once" );
+
+  double surv_rate = (double) surv_words / (double) HeapRegion::GrainWords;
+  _surv_rate[age_in_group] = surv_rate;
+  _surv_rate_pred[age_in_group]->add(surv_rate);
+  if ((size_t)age_in_group < _summary_surv_rates_len) {
+    _summary_surv_rates[age_in_group]->add(surv_rate);
+    if ((size_t)(age_in_group+1) > _summary_surv_rates_max_len)
+      _summary_surv_rates_max_len = age_in_group+1;
+  }
+}
+
+void
+SurvRateGroup::all_surviving_words_recorded(bool propagate) {
+  if (propagate && _curr_length > 0) { // conservative
+    double surv_rate = _surv_rate_pred[_curr_length-1]->last();
+
+#if 0
+    gclog_or_tty->print_cr("propagating %1.2lf from %d to %d",
+                  surv_rate, _curr_length, _array_length - 1);
+#endif // 0
+
+    for (size_t i = _curr_length; i < _array_length; ++i) {
+      guarantee( _surv_rate[i] <= 0.00001,
+                 "the slot should not have been updated" );
+      _surv_rate_pred[i]->add(surv_rate);
+    }
+  }
+
+  double accum = 0.0;
+  double pred = 0.0;
+  for (size_t i = 0; i < _array_length; ++i) {
+    pred = _g1p->get_new_prediction(_surv_rate_pred[i]);
+    if (pred > 1.0) pred = 1.0;
+    accum += pred;
+    _accum_surv_rate_pred[i] = accum;
+    // gclog_or_tty->print_cr("age %3d, accum %10.2lf", i, accum);
+  }
+  _last_pred = pred;
+}
+
+#ifndef PRODUCT
+void
+SurvRateGroup::print() {
+  gclog_or_tty->print_cr("Surv Rate Group: %s (%d entries, %d scan-only)",
+                _name, _curr_length, _scan_only_prefix);
+  for (size_t i = 0; i < _curr_length; ++i) {
+    gclog_or_tty->print_cr("    age %4d   surv rate %6.2lf %%   pred %6.2lf %%%s",
+                  i, _surv_rate[i] * 100.0,
+                  _g1p->get_new_prediction(_surv_rate_pred[i]) * 100.0,
+                  (i < _scan_only_prefix) ? " S-O" : "    ");
+  }
+}
+
+void
+SurvRateGroup::print_surv_rate_summary() {
+  size_t length = _summary_surv_rates_max_len;
+  if (length == 0)
+    return;
+
+  gclog_or_tty->print_cr("");
+  gclog_or_tty->print_cr("%s Rate Summary (for up to age %d)", _name, length-1);
+  gclog_or_tty->print_cr("      age range     survival rate (avg)      samples (avg)");
+  gclog_or_tty->print_cr("  ---------------------------------------------------------");
+
+  size_t index = 0;
+  size_t limit = MIN2((int) length, 10);
+  while (index < limit) {
+    gclog_or_tty->print_cr("           %4d                 %6.2lf%%             %6.2lf",
+                  index, _summary_surv_rates[index]->avg() * 100.0,
+                  (double) _summary_surv_rates[index]->num());
+    ++index;
+  }
+
+  gclog_or_tty->print_cr("  ---------------------------------------------------------");
+
+  int num = 0;
+  double sum = 0.0;
+  int samples = 0;
+  while (index < length) {
+    ++num;
+    sum += _summary_surv_rates[index]->avg() * 100.0;
+    samples += _summary_surv_rates[index]->num();
+    ++index;
+
+    if (index == length || num % 10 == 0) {
+      gclog_or_tty->print_cr("   %4d .. %4d                 %6.2lf%%             %6.2lf",
+                    (index-1) / 10 * 10, index-1, sum / (double) num,
+                    (double) samples / (double) num);
+      sum = 0.0;
+      num = 0;
+      samples = 0;
+    }
+  }
+
+  gclog_or_tty->print_cr("  ---------------------------------------------------------");
+}
+#endif // PRODUCT