1.1 --- a/src/share/vm/gc_implementation/g1/g1RemSet.cpp Mon Apr 27 12:33:57 2009 -0700
1.2 +++ b/src/share/vm/gc_implementation/g1/g1RemSet.cpp Mon Apr 27 16:52:18 2009 -0700
1.3 @@ -180,6 +180,7 @@
1.4 CardTableModRefBS *_ct_bs;
1.5 int _worker_i;
1.6 bool _try_claimed;
1.7 + size_t _min_skip_distance, _max_skip_distance;
1.8 public:
1.9 ScanRSClosure(OopsInHeapRegionClosure* oc, int worker_i) :
1.10 _oc(oc),
1.11 @@ -191,6 +192,8 @@
1.12 _g1h = G1CollectedHeap::heap();
1.13 _bot_shared = _g1h->bot_shared();
1.14 _ct_bs = (CardTableModRefBS*) (_g1h->barrier_set());
1.15 + _min_skip_distance = 16;
1.16 + _max_skip_distance = 2 * _g1h->n_par_threads() * _min_skip_distance;
1.17 }
1.18
1.19 void set_try_claimed() { _try_claimed = true; }
1.20 @@ -245,9 +248,13 @@
1.21 HeapRegionRemSetIterator* iter = _g1h->rem_set_iterator(_worker_i);
1.22 hrrs->init_iterator(iter);
1.23 size_t card_index;
1.24 + size_t skip_distance = 0, current_card = 0, jump_to_card = 0;
1.25 while (iter->has_next(card_index)) {
1.26 + if (current_card < jump_to_card) {
1.27 + ++current_card;
1.28 + continue;
1.29 + }
1.30 HeapWord* card_start = _g1h->bot_shared()->address_for_index(card_index);
1.31 -
1.32 #if 0
1.33 gclog_or_tty->print("Rem set iteration yielded card [" PTR_FORMAT ", " PTR_FORMAT ").\n",
1.34 card_start, card_start + CardTableModRefBS::card_size_in_words);
1.35 @@ -257,20 +264,28 @@
1.36 assert(card_region != NULL, "Yielding cards not in the heap?");
1.37 _cards++;
1.38
1.39 - if (!card_region->in_collection_set()) {
1.40 - // If the card is dirty, then we will scan it during updateRS.
1.41 - if (!_ct_bs->is_card_claimed(card_index) &&
1.42 - !_ct_bs->is_card_dirty(card_index)) {
1.43 - assert(_ct_bs->is_card_clean(card_index) ||
1.44 - _ct_bs->is_card_claimed(card_index) ||
1.45 - _ct_bs->is_card_deferred(card_index),
1.46 - "Card is either clean, claimed or deferred");
1.47 - if (_ct_bs->claim_card(card_index))
1.48 + // If the card is dirty, then we will scan it during updateRS.
1.49 + if (!card_region->in_collection_set() && !_ct_bs->is_card_dirty(card_index)) {
1.50 + if (!_ct_bs->is_card_claimed(card_index) && _ct_bs->claim_card(card_index)) {
1.51 scanCard(card_index, card_region);
1.52 - }
1.53 + } else if (_try_claimed) {
1.54 + if (jump_to_card == 0 || jump_to_card != current_card) {
1.55 + // We did some useful work in the previous iteration.
1.56 + // Decrease the distance.
1.57 + skip_distance = MAX2(skip_distance >> 1, _min_skip_distance);
1.58 + } else {
1.59 + // Previous iteration resulted in a claim failure.
1.60 + // Increase the distance.
1.61 + skip_distance = MIN2(skip_distance << 1, _max_skip_distance);
1.62 + }
1.63 + jump_to_card = current_card + skip_distance;
1.64 + }
1.65 }
1.66 + ++current_card;
1.67 }
1.68 - hrrs->set_iter_complete();
1.69 + if (!_try_claimed) {
1.70 + hrrs->set_iter_complete();
1.71 + }
1.72 return false;
1.73 }
1.74 // Set all cards back to clean.
