duke@435: /*
trims@1907:  * Copyright (c) 2001, 2008, Oracle and/or its affiliates. All rights reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
duke@435: # include "incls/_precompiled.incl"
duke@435: # include "incls/_psPermGen.cpp.incl"
duke@435: 
duke@435: PSPermGen::PSPermGen(ReservedSpace rs, size_t alignment,
duke@435:                      size_t initial_size, size_t min_size, size_t max_size,
duke@435:                      const char* gen_name, int level) :
duke@435:   PSOldGen(rs, alignment, initial_size, min_size, max_size, gen_name, level),
duke@435:   _last_used(0)
duke@435: {
duke@435:   assert(object_mark_sweep() != NULL, "Sanity");
duke@435: 
duke@435:   object_mark_sweep()->set_allowed_dead_ratio(PermMarkSweepDeadRatio);
duke@435:   _avg_size = new AdaptivePaddedAverage(AdaptivePermSizeWeight,
duke@435:                                         PermGenPadding);
duke@435: }
duke@435: 
duke@435: HeapWord* PSPermGen::allocate_permanent(size_t size) {
duke@435:   assert_locked_or_safepoint(Heap_lock);
duke@435:   HeapWord* obj = allocate_noexpand(size, false);
duke@435: 
duke@435:   if (obj == NULL) {
duke@435:     obj = expand_and_allocate(size, false);
duke@435:   }
duke@435: 
duke@435:   return obj;
duke@435: }
duke@435: 
duke@435: void PSPermGen::compute_new_size(size_t used_before_collection) {
duke@435:   // Update our padded average of objects allocated in perm
duke@435:   // gen between collections.
duke@435:   assert(used_before_collection >= _last_used,
duke@435:                                 "negative allocation amount since last GC?");
duke@435: 
duke@435:   const size_t alloc_since_last_gc = used_before_collection - _last_used;
duke@435:   _avg_size->sample(alloc_since_last_gc);
duke@435: 
duke@435:   const size_t current_live = used_in_bytes();
duke@435:   // Stash away the current amount live for the next call to this method.
duke@435:   _last_used = current_live;
duke@435: 
duke@435:   // We have different alignment constraints than the rest of the heap.
duke@435:   const size_t alignment = MAX2(MinPermHeapExpansion,
duke@435:                                 virtual_space()->alignment());
duke@435: 
duke@435:   // Compute the desired size:
duke@435:   //  The free space is the newly computed padded average,
duke@435:   //  so the desired size is what's live + the free space.
duke@435:   size_t desired_size = current_live + (size_t)_avg_size->padded_average();
duke@435:   desired_size = align_size_up(desired_size, alignment);
duke@435: 
duke@435:   // ...and no larger or smaller than our max and min allowed.
duke@435:   desired_size = MAX2(MIN2(desired_size, _max_gen_size), _min_gen_size);
duke@435:   assert(desired_size <= _max_gen_size, "just checking");
duke@435: 
duke@435:   const size_t size_before = _virtual_space->committed_size();
duke@435: 
duke@435:   if (desired_size == size_before) {
duke@435:     // no change, we're done
duke@435:     return;
duke@435:   }
duke@435: 
duke@435:   {
duke@435:     // We'll be growing or shrinking the heap:  in either case,
duke@435:     // we need to hold a lock.
duke@435:     MutexLocker x(ExpandHeap_lock);
duke@435:     if (desired_size > size_before) {
duke@435:       const size_t change_bytes = desired_size - size_before;
duke@435:       const size_t aligned_change_bytes =
duke@435:         align_size_up(change_bytes, alignment);
duke@435:       expand_by(aligned_change_bytes);
duke@435:     } else {
duke@435:       // Shrinking
duke@435:       const size_t change_bytes =
duke@435:         size_before - desired_size;
duke@435:       const size_t aligned_change_bytes = align_size_down(change_bytes, alignment);
duke@435:       shrink(aligned_change_bytes);
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   // While this code isn't controlled by AdaptiveSizePolicy, it's
duke@435:   // convenient to see all resizing decsions under the same flag.
duke@435:   if (PrintAdaptiveSizePolicy) {
duke@435:     ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
duke@435:     assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
duke@435: 
duke@435:     gclog_or_tty->print_cr("AdaptiveSizePolicy::perm generation size: "
duke@435:                            "collection: %d "
duke@435:                            "(" SIZE_FORMAT ") -> (" SIZE_FORMAT ") ",
duke@435:                            heap->total_collections(),
duke@435:                            size_before, _virtual_space->committed_size());
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: 
duke@435: void PSPermGen::move_and_update(ParCompactionManager* cm) {
duke@435:   PSParallelCompact::move_and_update(cm, PSParallelCompact::perm_space_id);
duke@435: }
duke@435: 
duke@435: void PSPermGen::precompact() {
duke@435:   // Reset start array first.
duke@435:   _start_array.reset();
duke@435:   object_mark_sweep()->precompact();
duke@435: }