1 /*

     2  * Copyright 1997-2006 Sun Microsystems, Inc.  All Rights Reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    20  * CA 95054 USA or visit www.sun.com if you need additional information or

    21  * have any questions.

    22  *

    23  */

    24 

    25 # include "incls/_precompiled.incl"

    26 # include "incls/_generation.cpp.incl"

    27 

    28 Generation::Generation(ReservedSpace rs, size_t initial_size, int level) :

    29   _level(level),

    30   _ref_processor(NULL) {

    31   if (!_virtual_space.initialize(rs, initial_size)) {

    32     vm_exit_during_initialization("Could not reserve enough space for "

    33                     "object heap");

    34   }

    35   _reserved = MemRegion((HeapWord*)_virtual_space.low_boundary(),

    36           (HeapWord*)_virtual_space.high_boundary());

    37 }

    38 

    39 GenerationSpec* Generation::spec() {

    40   GenCollectedHeap* gch = GenCollectedHeap::heap();

    41   assert(0 <= level() && level() < gch->_n_gens, "Bad gen level");

    42   return gch->_gen_specs[level()];

    43 }

    44 

    45 size_t Generation::max_capacity() const {

    46   return reserved().byte_size();

    47 }

    48 

    49 void Generation::print_heap_change(size_t prev_used) const {

    50   if (PrintGCDetails && Verbose) {

    51     gclog_or_tty->print(" "  SIZE_FORMAT

    52                         "->" SIZE_FORMAT

    53                         "("  SIZE_FORMAT ")",

    54                         prev_used, used(), capacity());

    55   } else {

    56     gclog_or_tty->print(" "  SIZE_FORMAT "K"

    57                         "->" SIZE_FORMAT "K"

    58                         "("  SIZE_FORMAT "K)",

    59                         prev_used / K, used() / K, capacity() / K);

    60   }

    61 }

    62 

    63 // By default we get a single threaded default reference processor;

    64 // generations needing multi-threaded refs discovery override this method.

    65 void Generation::ref_processor_init() {

    66   assert(_ref_processor == NULL, "a reference processor already exists");

    67   assert(!_reserved.is_empty(), "empty generation?");

    68   _ref_processor =

    69     new ReferenceProcessor(_reserved,                  // span

    70                            refs_discovery_is_atomic(), // atomic_discovery

    71                            refs_discovery_is_mt());    // mt_discovery

    72   if (_ref_processor == NULL) {

    73     vm_exit_during_initialization("Could not allocate ReferenceProcessor object");

    74   }

    75 }

    76 

    77 void Generation::print() const { print_on(tty); }

    78 

    79 void Generation::print_on(outputStream* st)  const {

    80   st->print(" %-20s", name());

    81   st->print(" total " SIZE_FORMAT "K, used " SIZE_FORMAT "K",

    82              capacity()/K, used()/K);

    83   st->print_cr(" [" INTPTR_FORMAT ", " INTPTR_FORMAT ", " INTPTR_FORMAT ")",

    84               _virtual_space.low_boundary(),

    85               _virtual_space.high(),

    86               _virtual_space.high_boundary());

    87 }

    88 

    89 void Generation::print_summary_info() { print_summary_info_on(tty); }

    90 

    91 void Generation::print_summary_info_on(outputStream* st) {

    92   StatRecord* sr = stat_record();

    93   double time = sr->accumulated_time.seconds();

    94   st->print_cr("[Accumulated GC generation %d time %3.7f secs, "

    95                "%d GC's, avg GC time %3.7f]",

    96                level(), time, sr->invocations,

    97                sr->invocations > 0 ? time / sr->invocations : 0.0);

    98 }

    99 

   100 // Utility iterator classes

   101 

   102 class GenerationIsInReservedClosure : public SpaceClosure {

   103  public:

   104   const void* _p;

   105   Space* sp;

   106   virtual void do_space(Space* s) {

   107     if (sp == NULL) {

   108       if (s->is_in_reserved(_p)) sp = s;

   109     }

   110   }

   111   GenerationIsInReservedClosure(const void* p) : _p(p), sp(NULL) {}

   112 };

   113 

   114 class GenerationIsInClosure : public SpaceClosure {

   115  public:

   116   const void* _p;

   117   Space* sp;

   118   virtual void do_space(Space* s) {

   119     if (sp == NULL) {

   120       if (s->is_in(_p)) sp = s;

   121     }

   122   }

   123   GenerationIsInClosure(const void* p) : _p(p), sp(NULL) {}

   124 };

   125 

   126 bool Generation::is_in(const void* p) const {

   127   GenerationIsInClosure blk(p);

   128   ((Generation*)this)->space_iterate(&blk);

   129   return blk.sp != NULL;

   130 }

   131 

   132 DefNewGeneration* Generation::as_DefNewGeneration() {

   133   assert((kind() == Generation::DefNew) ||

   134          (kind() == Generation::ParNew) ||

   135          (kind() == Generation::ASParNew),

   136     "Wrong youngest generation type");

   137   return (DefNewGeneration*) this;

   138 }

   139 

   140 Generation* Generation::next_gen() const {

   141   GenCollectedHeap* gch = GenCollectedHeap::heap();

   142   int next = level() + 1;

   143   if (next < gch->_n_gens) {

   144     return gch->_gens[next];

   145   } else {

   146     return NULL;

   147   }

   148 }

   149 

   150 size_t Generation::max_contiguous_available() const {

   151   // The largest number of contiguous free words in this or any higher generation.

   152   size_t max = 0;

   153   for (const Generation* gen = this; gen != NULL; gen = gen->next_gen()) {

   154     size_t avail = gen->contiguous_available();

   155     if (avail > max) {

   156       max = avail;

   157     }

   158   }

   159   return max;

   160 }

   161 

   162 bool Generation::promotion_attempt_is_safe(size_t promotion_in_bytes,

   163                                            bool not_used) const {

   164   if (PrintGC && Verbose) {

   165     gclog_or_tty->print_cr("Generation::promotion_attempt_is_safe"

   166                 " contiguous_available: " SIZE_FORMAT

   167                 " promotion_in_bytes: " SIZE_FORMAT,

   168                 max_contiguous_available(), promotion_in_bytes);

   169   }

   170   return max_contiguous_available() >= promotion_in_bytes;

   171 }

   172 

   173 // Ignores "ref" and calls allocate().

   174 oop Generation::promote(oop obj, size_t obj_size, oop* ref) {

   175   assert(obj_size == (size_t)obj->size(), "bad obj_size passed in");

   176 

   177 #ifndef PRODUCT

   178   if (Universe::heap()->promotion_should_fail()) {

   179     return NULL;

   180   }

   181 #endif  // #ifndef PRODUCT

   182 

   183   HeapWord* result = allocate(obj_size, false);

   184   if (result != NULL) {

   185     Copy::aligned_disjoint_words((HeapWord*)obj, result, obj_size);

   186     return oop(result);

   187   } else {

   188     GenCollectedHeap* gch = GenCollectedHeap::heap();

   189     return gch->handle_failed_promotion(this, obj, obj_size, ref);

   190   }

   191 }

   192 

   193 oop Generation::par_promote(int thread_num,

   194                             oop obj, markOop m, size_t word_sz) {

   195   // Could do a bad general impl here that gets a lock.  But no.

   196   ShouldNotCallThis();

   197   return NULL;

   198 }

   199 

   200 void Generation::par_promote_alloc_undo(int thread_num,

   201                                         HeapWord* obj, size_t word_sz) {

   202   // Could do a bad general impl here that gets a lock.  But no.

   203   guarantee(false, "No good general implementation.");

   204 }

   205 

   206 Space* Generation::space_containing(const void* p) const {

   207   GenerationIsInReservedClosure blk(p);

   208   // Cast away const

   209   ((Generation*)this)->space_iterate(&blk);

   210   return blk.sp;

   211 }

   212 

   213 // Some of these are mediocre general implementations.  Should be

   214 // overridden to get better performance.

   215 

   216 class GenerationBlockStartClosure : public SpaceClosure {

   217  public:

   218   const void* _p;

   219   HeapWord* _start;

   220   virtual void do_space(Space* s) {

   221     if (_start == NULL && s->is_in_reserved(_p)) {

   222       _start = s->block_start(_p);

   223     }

   224   }

   225   GenerationBlockStartClosure(const void* p) { _p = p; _start = NULL; }

   226 };

   227 

   228 HeapWord* Generation::block_start(const void* p) const {

   229   GenerationBlockStartClosure blk(p);

   230   // Cast away const

   231   ((Generation*)this)->space_iterate(&blk);

   232   return blk._start;

   233 }

   234 

   235 class GenerationBlockSizeClosure : public SpaceClosure {

   236  public:

   237   const HeapWord* _p;

   238   size_t size;

   239   virtual void do_space(Space* s) {

   240     if (size == 0 && s->is_in_reserved(_p)) {

   241       size = s->block_size(_p);

   242     }

   243   }

   244   GenerationBlockSizeClosure(const HeapWord* p) { _p = p; size = 0; }

   245 };

   246 

   247 size_t Generation::block_size(const HeapWord* p) const {

   248   GenerationBlockSizeClosure blk(p);

   249   // Cast away const

   250   ((Generation*)this)->space_iterate(&blk);

   251   assert(blk.size > 0, "seems reasonable");

   252   return blk.size;

   253 }

   254 

   255 class GenerationBlockIsObjClosure : public SpaceClosure {

   256  public:

   257   const HeapWord* _p;

   258   bool is_obj;

   259   virtual void do_space(Space* s) {

   260     if (!is_obj && s->is_in_reserved(_p)) {

   261       is_obj |= s->block_is_obj(_p);

   262     }

   263   }

   264   GenerationBlockIsObjClosure(const HeapWord* p) { _p = p; is_obj = false; }

   265 };

   266 

   267 bool Generation::block_is_obj(const HeapWord* p) const {

   268   GenerationBlockIsObjClosure blk(p);

   269   // Cast away const

   270   ((Generation*)this)->space_iterate(&blk);

   271   return blk.is_obj;

   272 }

   273 

   274 class GenerationOopIterateClosure : public SpaceClosure {

   275  public:

   276   OopClosure* cl;

   277   MemRegion mr;

   278   virtual void do_space(Space* s) {

   279     s->oop_iterate(mr, cl);

   280   }

   281   GenerationOopIterateClosure(OopClosure* _cl, MemRegion _mr) :

   282     cl(_cl), mr(_mr) {}

   283 };

   284 

   285 void Generation::oop_iterate(OopClosure* cl) {

   286   GenerationOopIterateClosure blk(cl, _reserved);

   287   space_iterate(&blk);

   288 }

   289 

   290 void Generation::oop_iterate(MemRegion mr, OopClosure* cl) {

   291   GenerationOopIterateClosure blk(cl, mr);

   292   space_iterate(&blk);

   293 }

   294 

   295 void Generation::younger_refs_in_space_iterate(Space* sp,

   296                                                OopsInGenClosure* cl) {

   297   GenRemSet* rs = SharedHeap::heap()->rem_set();

   298   rs->younger_refs_in_space_iterate(sp, cl);

   299 }

   300 

   301 class GenerationObjIterateClosure : public SpaceClosure {

   302  private:

   303   ObjectClosure* _cl;

   304  public:

   305   virtual void do_space(Space* s) {

   306     s->object_iterate(_cl);

   307   }

   308   GenerationObjIterateClosure(ObjectClosure* cl) : _cl(cl) {}

   309 };

   310 

   311 void Generation::object_iterate(ObjectClosure* cl) {

   312   GenerationObjIterateClosure blk(cl);

   313   space_iterate(&blk);

   314 }

   315 

   316 void Generation::prepare_for_compaction(CompactPoint* cp) {

   317   // Generic implementation, can be specialized

   318   CompactibleSpace* space = first_compaction_space();

   319   while (space != NULL) {

   320     space->prepare_for_compaction(cp);

   321     space = space->next_compaction_space();

   322   }

   323 }

   324 

   325 class AdjustPointersClosure: public SpaceClosure {

   326  public:

   327   void do_space(Space* sp) {

   328     sp->adjust_pointers();

   329   }

   330 };

   331 

   332 void Generation::adjust_pointers() {

   333   // Note that this is done over all spaces, not just the compactible

   334   // ones.

   335   AdjustPointersClosure blk;

   336   space_iterate(&blk, true);

   337 }

   338 

   339 void Generation::compact() {

   340   CompactibleSpace* sp = first_compaction_space();

   341   while (sp != NULL) {

   342     sp->compact();

   343     sp = sp->next_compaction_space();

   344   }

   345 }

   346 

   347 CardGeneration::CardGeneration(ReservedSpace rs, size_t initial_byte_size,

   348                                int level,

   349                                GenRemSet* remset) :

   350   Generation(rs, initial_byte_size, level), _rs(remset)

   351 {

   352   HeapWord* start = (HeapWord*)rs.base();

   353   size_t reserved_byte_size = rs.size();

   354   assert((uintptr_t(start) & 3) == 0, "bad alignment");

   355   assert((reserved_byte_size & 3) == 0, "bad alignment");

   356   MemRegion reserved_mr(start, heap_word_size(reserved_byte_size));

   357   _bts = new BlockOffsetSharedArray(reserved_mr,

   358                                     heap_word_size(initial_byte_size));

   359   MemRegion committed_mr(start, heap_word_size(initial_byte_size));

   360   _rs->resize_covered_region(committed_mr);

   361   if (_bts == NULL)

   362     vm_exit_during_initialization("Could not allocate a BlockOffsetArray");

   363 

   364   // Verify that the start and end of this generation is the start of a card.

   365   // If this wasn't true, a single card could span more than on generation,

   366   // which would cause problems when we commit/uncommit memory, and when we

   367   // clear and dirty cards.

   368   guarantee(_rs->is_aligned(reserved_mr.start()), "generation must be card aligned");

   369   if (reserved_mr.end() != Universe::heap()->reserved_region().end()) {

   370     // Don't check at the very end of the heap as we'll assert that we're probing off

   371     // the end if we try.

   372     guarantee(_rs->is_aligned(reserved_mr.end()), "generation must be card aligned");

   373   }

   374 }

   375 

   376 

   377 // No young generation references, clear this generation's cards.

   378 void CardGeneration::clear_remembered_set() {

   379   _rs->clear(reserved());

   380 }

   381 

   382 

   383 // Objects in this generation may have moved, invalidate this

   384 // generation's cards.

   385 void CardGeneration::invalidate_remembered_set() {

   386   _rs->invalidate(used_region());

   387 }

   388 

   389 

   390 // Currently nothing to do.

   391 void CardGeneration::prepare_for_verify() {}

   392 

   393 

   394 void OneContigSpaceCardGeneration::collect(bool   full,

   395                                            bool   clear_all_soft_refs,

   396                                            size_t size,

   397                                            bool   is_tlab) {

   398   SpecializationStats::clear();

   399   // Temporarily expand the span of our ref processor, so

   400   // refs discovery is over the entire heap, not just this generation

   401   ReferenceProcessorSpanMutator

   402     x(ref_processor(), GenCollectedHeap::heap()->reserved_region());

   403   GenMarkSweep::invoke_at_safepoint(_level, ref_processor(), clear_all_soft_refs);

   404   SpecializationStats::print();

   405 }

   406 

   407 HeapWord*

   408 OneContigSpaceCardGeneration::expand_and_allocate(size_t word_size,

   409                                                   bool is_tlab,

   410                                                   bool parallel) {

   411   assert(!is_tlab, "OneContigSpaceCardGeneration does not support TLAB allocation");

   412   if (parallel) {

   413     MutexLocker x(ParGCRareEvent_lock);

   414     HeapWord* result = NULL;

   415     size_t byte_size = word_size * HeapWordSize;

   416     while (true) {

   417       expand(byte_size, _min_heap_delta_bytes);

   418       if (GCExpandToAllocateDelayMillis > 0) {

   419         os::sleep(Thread::current(), GCExpandToAllocateDelayMillis, false);

   420       }

   421       result = _the_space->par_allocate(word_size);

   422       if ( result != NULL) {

   423         return result;

   424       } else {

   425         // If there's not enough expansion space available, give up.

   426         if (_virtual_space.uncommitted_size() < byte_size) {

   427           return NULL;

   428         }

   429         // else try again

   430       }

   431     }

   432   } else {

   433     expand(word_size*HeapWordSize, _min_heap_delta_bytes);

   434     return _the_space->allocate(word_size);

   435   }

   436 }

   437 

   438 void OneContigSpaceCardGeneration::expand(size_t bytes, size_t expand_bytes) {

   439   GCMutexLocker x(ExpandHeap_lock);

   440   size_t aligned_bytes  = ReservedSpace::page_align_size_up(bytes);

   441   size_t aligned_expand_bytes = ReservedSpace::page_align_size_up(expand_bytes);

   442   bool success = false;

   443   if (aligned_expand_bytes > aligned_bytes) {

   444     success = grow_by(aligned_expand_bytes);

   445   }

   446   if (!success) {

   447     success = grow_by(aligned_bytes);

   448   }

   449   if (!success) {

   450     grow_to_reserved();

   451   }

   452   if (GC_locker::is_active()) {

   453     if (PrintGC && Verbose) {

   454       gclog_or_tty->print_cr("Garbage collection disabled, expanded heap instead");

   455     }

   456   }

   457 }

   458 

   459 

   460 void OneContigSpaceCardGeneration::shrink(size_t bytes) {

   461   assert_locked_or_safepoint(ExpandHeap_lock);

   462   size_t size = ReservedSpace::page_align_size_down(bytes);

   463   if (size > 0) {

   464     shrink_by(size);

   465   }

   466 }

   467 

   468 

   469 size_t OneContigSpaceCardGeneration::capacity() const {

   470   return _the_space->capacity();

   471 }

   472 

   473 

   474 size_t OneContigSpaceCardGeneration::used() const {

   475   return _the_space->used();

   476 }

   477 

   478 

   479 size_t OneContigSpaceCardGeneration::free() const {

   480   return _the_space->free();

   481 }

   482 

   483 MemRegion OneContigSpaceCardGeneration::used_region() const {

   484   return the_space()->used_region();

   485 }

   486 

   487 size_t OneContigSpaceCardGeneration::unsafe_max_alloc_nogc() const {

   488   return _the_space->free();

   489 }

   490 

   491 size_t OneContigSpaceCardGeneration::contiguous_available() const {

   492   return _the_space->free() + _virtual_space.uncommitted_size();

   493 }

   494 

   495 bool OneContigSpaceCardGeneration::grow_by(size_t bytes) {

   496   assert_locked_or_safepoint(ExpandHeap_lock);

   497   bool result = _virtual_space.expand_by(bytes);

   498   if (result) {

   499     size_t new_word_size =

   500        heap_word_size(_virtual_space.committed_size());

   501     MemRegion mr(_the_space->bottom(), new_word_size);

   502     // Expand card table

   503     Universe::heap()->barrier_set()->resize_covered_region(mr);

   504     // Expand shared block offset array

   505     _bts->resize(new_word_size);

   506 

   507     // Fix for bug #4668531

   508     MemRegion mangle_region(_the_space->end(), (HeapWord*)_virtual_space.high());

   509     _the_space->mangle_region(mangle_region);

   510 

   511     // Expand space -- also expands space's BOT

   512     // (which uses (part of) shared array above)

   513     _the_space->set_end((HeapWord*)_virtual_space.high());

   514 

   515     // update the space and generation capacity counters

   516     update_counters();

   517 

   518     if (Verbose && PrintGC) {

   519       size_t new_mem_size = _virtual_space.committed_size();

   520       size_t old_mem_size = new_mem_size - bytes;

   521       gclog_or_tty->print_cr("Expanding %s from " SIZE_FORMAT "K by "

   522                       SIZE_FORMAT "K to " SIZE_FORMAT "K",

   523                       name(), old_mem_size/K, bytes/K, new_mem_size/K);

   524     }

   525   }

   526   return result;

   527 }

   528 

   529 

   530 bool OneContigSpaceCardGeneration::grow_to_reserved() {

   531   assert_locked_or_safepoint(ExpandHeap_lock);

   532   bool success = true;

   533   const size_t remaining_bytes = _virtual_space.uncommitted_size();

   534   if (remaining_bytes > 0) {

   535     success = grow_by(remaining_bytes);

   536     DEBUG_ONLY(if (!success) warning("grow to reserved failed");)

   537   }

   538   return success;

   539 }

   540 

   541 void OneContigSpaceCardGeneration::shrink_by(size_t bytes) {

   542   assert_locked_or_safepoint(ExpandHeap_lock);

   543   // Shrink committed space

   544   _virtual_space.shrink_by(bytes);

   545   // Shrink space; this also shrinks the space's BOT

   546   _the_space->set_end((HeapWord*) _virtual_space.high());

   547   size_t new_word_size = heap_word_size(_the_space->capacity());

   548   // Shrink the shared block offset array

   549   _bts->resize(new_word_size);

   550   MemRegion mr(_the_space->bottom(), new_word_size);

   551   // Shrink the card table

   552   Universe::heap()->barrier_set()->resize_covered_region(mr);

   553 

   554   if (Verbose && PrintGC) {

   555     size_t new_mem_size = _virtual_space.committed_size();

   556     size_t old_mem_size = new_mem_size + bytes;

   557     gclog_or_tty->print_cr("Shrinking %s from " SIZE_FORMAT "K to " SIZE_FORMAT "K",

   558                   name(), old_mem_size/K, new_mem_size/K);

   559   }

   560 }

   561 

   562 // Currently nothing to do.

   563 void OneContigSpaceCardGeneration::prepare_for_verify() {}

   564 

   565 

   566 void OneContigSpaceCardGeneration::object_iterate(ObjectClosure* blk) {

   567   _the_space->object_iterate(blk);

   568 }

   569 

   570 void OneContigSpaceCardGeneration::space_iterate(SpaceClosure* blk,

   571                                                  bool usedOnly) {

   572   blk->do_space(_the_space);

   573 }

   574 

   575 void OneContigSpaceCardGeneration::object_iterate_since_last_GC(ObjectClosure* blk) {

   576   // Deal with delayed initialization of _the_space,

   577   // and lack of initialization of _last_gc.

   578   if (_last_gc.space() == NULL) {

   579     assert(the_space() != NULL, "shouldn't be NULL");

   580     _last_gc = the_space()->bottom_mark();

   581   }

   582   the_space()->object_iterate_from(_last_gc, blk);

   583 }

   584 

   585 void OneContigSpaceCardGeneration::younger_refs_iterate(OopsInGenClosure* blk) {

   586   blk->set_generation(this);

   587   younger_refs_in_space_iterate(_the_space, blk);

   588   blk->reset_generation();

   589 }

   590 

   591 void OneContigSpaceCardGeneration::save_marks() {

   592   _the_space->set_saved_mark();

   593 }

   594 

   595 

   596 void OneContigSpaceCardGeneration::reset_saved_marks() {

   597   _the_space->reset_saved_mark();

   598 }

   599 

   600 

   601 bool OneContigSpaceCardGeneration::no_allocs_since_save_marks() {

   602   return _the_space->saved_mark_at_top();

   603 }

   604 

   605 #define OneContig_SINCE_SAVE_MARKS_ITERATE_DEFN(OopClosureType, nv_suffix)      \

   606                                                                                 \

   607 void OneContigSpaceCardGeneration::                                             \

   608 oop_since_save_marks_iterate##nv_suffix(OopClosureType* blk) {                  \

   609   blk->set_generation(this);                                                    \

   610   _the_space->oop_since_save_marks_iterate##nv_suffix(blk);                     \

   611   blk->reset_generation();                                                      \

   612   save_marks();                                                                 \

   613 }

   614 

   615 ALL_SINCE_SAVE_MARKS_CLOSURES(OneContig_SINCE_SAVE_MARKS_ITERATE_DEFN)

   616 

   617 #undef OneContig_SINCE_SAVE_MARKS_ITERATE_DEFN

   618 

   619 

   620 void OneContigSpaceCardGeneration::gc_epilogue(bool full) {

   621   _last_gc = WaterMark(the_space(), the_space()->top());

   622 

   623   // update the generation and space performance counters

   624   update_counters();

   625 }

   626 

   627 void OneContigSpaceCardGeneration::verify(bool allow_dirty) {

   628   the_space()->verify(allow_dirty);

   629 }

   630 

   631 void OneContigSpaceCardGeneration::print_on(outputStream* st)  const {

   632   Generation::print_on(st);

   633   st->print("   the");

   634   the_space()->print_on(st);

   635 }