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src/share/vm/memory/generation.cpp

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rev 7474 : imported patch separateCardGeneration

@@ -359,246 +359,5 @@
   while (sp != NULL) {
     sp->compact();
     sp = sp->next_compaction_space();
   }
 }
-
-CardGeneration::CardGeneration(ReservedSpace rs, size_t initial_byte_size,
-                               int level,
-                               GenRemSet* remset) :
-  Generation(rs, initial_byte_size, level), _rs(remset),
-  _shrink_factor(0), _min_heap_delta_bytes(), _capacity_at_prologue(),
-  _used_at_prologue()
-{
-  HeapWord* start = (HeapWord*)rs.base();
-  size_t reserved_byte_size = rs.size();
-  assert((uintptr_t(start) & 3) == 0, "bad alignment");
-  assert((reserved_byte_size & 3) == 0, "bad alignment");
-  MemRegion reserved_mr(start, heap_word_size(reserved_byte_size));
-  _bts = new BlockOffsetSharedArray(reserved_mr,
-                                    heap_word_size(initial_byte_size));
-  MemRegion committed_mr(start, heap_word_size(initial_byte_size));
-  _rs->resize_covered_region(committed_mr);
-  if (_bts == NULL)
-    vm_exit_during_initialization("Could not allocate a BlockOffsetArray");
-
-  // Verify that the start and end of this generation is the start of a card.
-  // If this wasn't true, a single card could span more than on generation,
-  // which would cause problems when we commit/uncommit memory, and when we
-  // clear and dirty cards.
-  guarantee(_rs->is_aligned(reserved_mr.start()), "generation must be card aligned");
-  if (reserved_mr.end() != Universe::heap()->reserved_region().end()) {
-    // Don't check at the very end of the heap as we'll assert that we're probing off
-    // the end if we try.
-    guarantee(_rs->is_aligned(reserved_mr.end()), "generation must be card aligned");
-  }
-  _min_heap_delta_bytes = MinHeapDeltaBytes;
-  _capacity_at_prologue = initial_byte_size;
-  _used_at_prologue = 0;
-}
-
-bool CardGeneration::expand(size_t bytes, size_t expand_bytes) {
-  assert_locked_or_safepoint(Heap_lock);
-  if (bytes == 0) {
-    return true;  // That's what grow_by(0) would return
-  }
-  size_t aligned_bytes  = ReservedSpace::page_align_size_up(bytes);
-  if (aligned_bytes == 0){
-    // The alignment caused the number of bytes to wrap.  An expand_by(0) will
-    // return true with the implication that an expansion was done when it
-    // was not.  A call to expand implies a best effort to expand by "bytes"
-    // but not a guarantee.  Align down to give a best effort.  This is likely
-    // the most that the generation can expand since it has some capacity to
-    // start with.
-    aligned_bytes = ReservedSpace::page_align_size_down(bytes);
-  }
-  size_t aligned_expand_bytes = ReservedSpace::page_align_size_up(expand_bytes);
-  bool success = false;
-  if (aligned_expand_bytes > aligned_bytes) {
-    success = grow_by(aligned_expand_bytes);
-  }
-  if (!success) {
-    success = grow_by(aligned_bytes);
-  }
-  if (!success) {
-    success = grow_to_reserved();
-  }
-  if (PrintGC && Verbose) {
-    if (success && GC_locker::is_active_and_needs_gc()) {
-      gclog_or_tty->print_cr("Garbage collection disabled, expanded heap instead");
-    }
-  }
-
-  return success;
-}
-
-
-// No young generation references, clear this generation's cards.
-void CardGeneration::clear_remembered_set() {
-  _rs->clear(reserved());
-}
-
-
-// Objects in this generation may have moved, invalidate this
-// generation's cards.
-void CardGeneration::invalidate_remembered_set() {
-  _rs->invalidate(used_region());
-}
-
-
-void CardGeneration::compute_new_size() {
-  assert(_shrink_factor <= 100, "invalid shrink factor");
-  size_t current_shrink_factor = _shrink_factor;
-  _shrink_factor = 0;
-
-  // We don't have floating point command-line arguments
-  // Note:  argument processing ensures that MinHeapFreeRatio < 100.
-  const double minimum_free_percentage = MinHeapFreeRatio / 100.0;
-  const double maximum_used_percentage = 1.0 - minimum_free_percentage;
-
-  // Compute some numbers about the state of the heap.
-  const size_t used_after_gc = used();
-  const size_t capacity_after_gc = capacity();
-
-  const double min_tmp = used_after_gc / maximum_used_percentage;
-  size_t minimum_desired_capacity = (size_t)MIN2(min_tmp, double(max_uintx));
-  // Don't shrink less than the initial generation size
-  minimum_desired_capacity = MAX2(minimum_desired_capacity,
-                                  spec()->init_size());
-  assert(used_after_gc <= minimum_desired_capacity, "sanity check");
-
-  if (PrintGC && Verbose) {
-    const size_t free_after_gc = free();
-    const double free_percentage = ((double)free_after_gc) / capacity_after_gc;
-    gclog_or_tty->print_cr("TenuredGeneration::compute_new_size: ");
-    gclog_or_tty->print_cr("  "
-                  "  minimum_free_percentage: %6.2f"
-                  "  maximum_used_percentage: %6.2f",
-                  minimum_free_percentage,
-                  maximum_used_percentage);
-    gclog_or_tty->print_cr("  "
-                  "   free_after_gc   : %6.1fK"
-                  "   used_after_gc   : %6.1fK"
-                  "   capacity_after_gc   : %6.1fK",
-                  free_after_gc / (double) K,
-                  used_after_gc / (double) K,
-                  capacity_after_gc / (double) K);
-    gclog_or_tty->print_cr("  "
-                  "   free_percentage: %6.2f",
-                  free_percentage);
-  }
-
-  if (capacity_after_gc < minimum_desired_capacity) {
-    // If we have less free space than we want then expand
-    size_t expand_bytes = minimum_desired_capacity - capacity_after_gc;
-    // Don't expand unless it's significant
-    if (expand_bytes >= _min_heap_delta_bytes) {
-      expand(expand_bytes, 0); // safe if expansion fails
-    }
-    if (PrintGC && Verbose) {
-      gclog_or_tty->print_cr("    expanding:"
-                    "  minimum_desired_capacity: %6.1fK"
-                    "  expand_bytes: %6.1fK"
-                    "  _min_heap_delta_bytes: %6.1fK",
-                    minimum_desired_capacity / (double) K,
-                    expand_bytes / (double) K,
-                    _min_heap_delta_bytes / (double) K);
-    }
-    return;
-  }
-
-  // No expansion, now see if we want to shrink
-  size_t shrink_bytes = 0;
-  // We would never want to shrink more than this
-  size_t max_shrink_bytes = capacity_after_gc - minimum_desired_capacity;
-
-  if (MaxHeapFreeRatio < 100) {
-    const double maximum_free_percentage = MaxHeapFreeRatio / 100.0;
-    const double minimum_used_percentage = 1.0 - maximum_free_percentage;
-    const double max_tmp = used_after_gc / minimum_used_percentage;
-    size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
-    maximum_desired_capacity = MAX2(maximum_desired_capacity,
-                                    spec()->init_size());
-    if (PrintGC && Verbose) {
-      gclog_or_tty->print_cr("  "
-                             "  maximum_free_percentage: %6.2f"
-                             "  minimum_used_percentage: %6.2f",
-                             maximum_free_percentage,
-                             minimum_used_percentage);
-      gclog_or_tty->print_cr("  "
-                             "  _capacity_at_prologue: %6.1fK"
-                             "  minimum_desired_capacity: %6.1fK"
-                             "  maximum_desired_capacity: %6.1fK",
-                             _capacity_at_prologue / (double) K,
-                             minimum_desired_capacity / (double) K,
-                             maximum_desired_capacity / (double) K);
-    }
-    assert(minimum_desired_capacity <= maximum_desired_capacity,
-           "sanity check");
-
-    if (capacity_after_gc > maximum_desired_capacity) {
-      // Capacity too large, compute shrinking size
-      shrink_bytes = capacity_after_gc - maximum_desired_capacity;
-      // We don't want shrink all the way back to initSize if people call
-      // System.gc(), because some programs do that between "phases" and then
-      // we'd just have to grow the heap up again for the next phase.  So we
-      // damp the shrinking: 0% on the first call, 10% on the second call, 40%
-      // on the third call, and 100% by the fourth call.  But if we recompute
-      // size without shrinking, it goes back to 0%.
-      shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
-      assert(shrink_bytes <= max_shrink_bytes, "invalid shrink size");
-      if (current_shrink_factor == 0) {
-        _shrink_factor = 10;
-      } else {
-        _shrink_factor = MIN2(current_shrink_factor * 4, (size_t) 100);
-      }
-      if (PrintGC && Verbose) {
-        gclog_or_tty->print_cr("  "
-                      "  shrinking:"
-                      "  initSize: %.1fK"
-                      "  maximum_desired_capacity: %.1fK",
-                      spec()->init_size() / (double) K,
-                      maximum_desired_capacity / (double) K);
-        gclog_or_tty->print_cr("  "
-                      "  shrink_bytes: %.1fK"
-                      "  current_shrink_factor: " SIZE_FORMAT
-                      "  new shrink factor: " SIZE_FORMAT
-                      "  _min_heap_delta_bytes: %.1fK",
-                      shrink_bytes / (double) K,
-                      current_shrink_factor,
-                      _shrink_factor,
-                      _min_heap_delta_bytes / (double) K);
-      }
-    }
-  }
-
-  if (capacity_after_gc > _capacity_at_prologue) {
-    // We might have expanded for promotions, in which case we might want to
-    // take back that expansion if there's room after GC.  That keeps us from
-    // stretching the heap with promotions when there's plenty of room.
-    size_t expansion_for_promotion = capacity_after_gc - _capacity_at_prologue;
-    expansion_for_promotion = MIN2(expansion_for_promotion, max_shrink_bytes);
-    // We have two shrinking computations, take the largest
-    shrink_bytes = MAX2(shrink_bytes, expansion_for_promotion);
-    assert(shrink_bytes <= max_shrink_bytes, "invalid shrink size");
-    if (PrintGC && Verbose) {
-      gclog_or_tty->print_cr("  "
-                             "  aggressive shrinking:"
-                             "  _capacity_at_prologue: %.1fK"
-                             "  capacity_after_gc: %.1fK"
-                             "  expansion_for_promotion: %.1fK"
-                             "  shrink_bytes: %.1fK",
-                             capacity_after_gc / (double) K,
-                             _capacity_at_prologue / (double) K,
-                             expansion_for_promotion / (double) K,
-                             shrink_bytes / (double) K);
-    }
-  }
-  // Don't shrink unless it's significant
-  if (shrink_bytes >= _min_heap_delta_bytes) {
-    shrink(shrink_bytes);
-  }
-}
-
-// Currently nothing to do.
-void CardGeneration::prepare_for_verify() {}
-
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