jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/parallelScavenge/adjoiningGenerations.cpp@fb69749583e8

     1 /*

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

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

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    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).

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

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    25 #include "precompiled.hpp"

    26 #include "gc_implementation/parallelScavenge/adjoiningGenerations.hpp"

    27 #include "gc_implementation/parallelScavenge/adjoiningVirtualSpaces.hpp"

    28 #include "gc_implementation/parallelScavenge/generationSizer.hpp"

    29 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"

    31 // If boundary moving is being used, create the young gen and old

    32 // gen with ASPSYoungGen and ASPSOldGen, respectively.  Revert to

    33 // the old behavior otherwise (with PSYoungGen and PSOldGen).

    35 AdjoiningGenerations::AdjoiningGenerations(ReservedSpace old_young_rs,

    36                                            GenerationSizer* policy,

    37                                            size_t alignment) :

    38   _virtual_spaces(old_young_rs, policy->min_gen1_size(),

    39                   policy->min_gen0_size(), alignment) {

    40   size_t init_low_byte_size = policy->initial_gen1_size();

    41   size_t min_low_byte_size = policy->min_gen1_size();

    42   size_t max_low_byte_size = policy->max_gen1_size();

    43   size_t init_high_byte_size = policy->initial_gen0_size();

    44   size_t min_high_byte_size = policy->min_gen0_size();

    45   size_t max_high_byte_size = policy->max_gen0_size();

    47   assert(min_low_byte_size <= init_low_byte_size &&

    48          init_low_byte_size <= max_low_byte_size, "Parameter check");

    49   assert(min_high_byte_size <= init_high_byte_size &&

    50          init_high_byte_size <= max_high_byte_size, "Parameter check");

    51   // Create the generations differently based on the option to

    52   // move the boundary.

    53   if (UseAdaptiveGCBoundary) {

    54     // Initialize the adjoining virtual spaces.  Then pass the

    55     // a virtual to each generation for initialization of the

    56     // generation.

    58     // Does the actual creation of the virtual spaces

    59     _virtual_spaces.initialize(max_low_byte_size,

    60                                init_low_byte_size,

    61                                init_high_byte_size);

    63     // Place the young gen at the high end.  Passes in the virtual space.

    64     _young_gen = new ASPSYoungGen(_virtual_spaces.high(),

    65                                   _virtual_spaces.high()->committed_size(),

    66                                   min_high_byte_size,

    67                                   _virtual_spaces.high_byte_size_limit());

    69     // Place the old gen at the low end. Passes in the virtual space.

    70     _old_gen = new ASPSOldGen(_virtual_spaces.low(),

    71                               _virtual_spaces.low()->committed_size(),

    72                               min_low_byte_size,

    73                               _virtual_spaces.low_byte_size_limit(),

    74                               "old", 1);

    76     young_gen()->initialize_work();

    77     assert(young_gen()->reserved().byte_size() <= young_gen()->gen_size_limit(),

    78      "Consistency check");

    79     assert(old_young_rs.size() >= young_gen()->gen_size_limit(),

    80      "Consistency check");

    82     old_gen()->initialize_work("old", 1);

    83     assert(old_gen()->reserved().byte_size() <= old_gen()->gen_size_limit(),

    84      "Consistency check");

    85     assert(old_young_rs.size() >= old_gen()->gen_size_limit(),

    86      "Consistency check");

    87   } else {

    89     // Layout the reserved space for the generations.

    90     ReservedSpace old_rs   =

    91       virtual_spaces()->reserved_space().first_part(max_low_byte_size);

    92     ReservedSpace heap_rs  =

    93       virtual_spaces()->reserved_space().last_part(max_low_byte_size);

    94     ReservedSpace young_rs = heap_rs.first_part(max_high_byte_size);

    95     assert(young_rs.size() == heap_rs.size(), "Didn't reserve all of the heap");

    97     // Create the generations.  Virtual spaces are not passed in.

    98     _young_gen = new PSYoungGen(init_high_byte_size,

    99                                 min_high_byte_size,

   100                                 max_high_byte_size);

   101     _old_gen = new PSOldGen(init_low_byte_size,

   102                             min_low_byte_size,

   103                             max_low_byte_size,

   104                             "old", 1);

   106     // The virtual spaces are created by the initialization of the gens.

   107     _young_gen->initialize(young_rs, alignment);

   108     assert(young_gen()->gen_size_limit() == young_rs.size(),

   109       "Consistency check");

   110     _old_gen->initialize(old_rs, alignment, "old", 1);

   111     assert(old_gen()->gen_size_limit() == old_rs.size(), "Consistency check");

   112   }

   113 }

   115 size_t AdjoiningGenerations::reserved_byte_size() {

   116   return virtual_spaces()->reserved_space().size();

   117 }

   120 // Make checks on the current sizes of the generations and

   121 // the contraints on the sizes of the generations.  Push

   122 // up the boundary within the contraints.  A partial

   123 // push can occur.

   124 void AdjoiningGenerations::request_old_gen_expansion(size_t expand_in_bytes) {

   125   assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

   127   assert_lock_strong(ExpandHeap_lock);

   128   assert_locked_or_safepoint(Heap_lock);

   130   // These sizes limit the amount the boundaries can move.  Effectively,

   131   // the generation says how much it is willing to yield to the other

   132   // generation.

   133   const size_t young_gen_available = young_gen()->available_for_contraction();

   134   const size_t old_gen_available = old_gen()->available_for_expansion();

   135   const size_t alignment = virtual_spaces()->alignment();

   136   size_t change_in_bytes = MIN3(young_gen_available,

   137                                 old_gen_available,

   138                                 align_size_up_(expand_in_bytes, alignment));

   140   if (change_in_bytes == 0) {

   141     return;

   142   }

   144   if (TraceAdaptiveGCBoundary) {

   145     gclog_or_tty->print_cr("Before expansion of old gen with boundary move");

   146     gclog_or_tty->print_cr("  Requested change: " SIZE_FORMAT_HEX "  Attempted change: " SIZE_FORMAT_HEX,

   147       expand_in_bytes, change_in_bytes);

   148     if (!PrintHeapAtGC) {

   149       Universe::print_on(gclog_or_tty);

   150     }

   151     gclog_or_tty->print_cr("  PSOldGen max size: " SIZE_FORMAT "K",

   152       old_gen()->max_gen_size()/K);

   153   }

   155   // Move the boundary between the generations up (smaller young gen).

   156   if (virtual_spaces()->adjust_boundary_up(change_in_bytes)) {

   157     young_gen()->reset_after_change();

   158     old_gen()->reset_after_change();

   159   }

   161   // The total reserved for the generations should match the sum

   162   // of the two even if the boundary is moving.

   163   assert(reserved_byte_size() ==

   164          old_gen()->max_gen_size() + young_gen()->max_size(),

   165          "Space is missing");

   166   young_gen()->space_invariants();

   167   old_gen()->space_invariants();

   169   if (TraceAdaptiveGCBoundary) {

   170     gclog_or_tty->print_cr("After expansion of old gen with boundary move");

   171     if (!PrintHeapAtGC) {

   172       Universe::print_on(gclog_or_tty);

   173     }

   174     gclog_or_tty->print_cr("  PSOldGen max size: " SIZE_FORMAT "K",

   175       old_gen()->max_gen_size()/K);

   176   }

   177 }

   179 // See comments on request_old_gen_expansion()

   180 bool AdjoiningGenerations::request_young_gen_expansion(size_t expand_in_bytes) {

   181   assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

   183   // If eden is not empty, the boundary can be moved but no advantage

   184   // can be made of the move since eden cannot be moved.

   185   if (!young_gen()->eden_space()->is_empty()) {

   186     return false;

   187   }

   190   bool result = false;

   191   const size_t young_gen_available = young_gen()->available_for_expansion();

   192   const size_t old_gen_available = old_gen()->available_for_contraction();

   193   const size_t alignment = virtual_spaces()->alignment();

   194   size_t change_in_bytes = MIN3(young_gen_available,

   195                                 old_gen_available,

   196                                 align_size_up_(expand_in_bytes, alignment));

   198   if (change_in_bytes == 0) {

   199     return false;

   200   }

   202   if (TraceAdaptiveGCBoundary) {

   203     gclog_or_tty->print_cr("Before expansion of young gen with boundary move");

   204     gclog_or_tty->print_cr("  Requested change: " SIZE_FORMAT_HEX "  Attempted change: " SIZE_FORMAT_HEX,

   205       expand_in_bytes, change_in_bytes);

   206     if (!PrintHeapAtGC) {

   207       Universe::print_on(gclog_or_tty);

   208     }

   209     gclog_or_tty->print_cr("  PSYoungGen max size: " SIZE_FORMAT "K",

   210       young_gen()->max_size()/K);

   211   }

   213   // Move the boundary between the generations down (smaller old gen).

   214   MutexLocker x(ExpandHeap_lock);

   215   if (virtual_spaces()->adjust_boundary_down(change_in_bytes)) {

   216     young_gen()->reset_after_change();

   217     old_gen()->reset_after_change();

   218     result = true;

   219   }

   221   // The total reserved for the generations should match the sum

   222   // of the two even if the boundary is moving.

   223   assert(reserved_byte_size() ==

   224          old_gen()->max_gen_size() + young_gen()->max_size(),

   225          "Space is missing");

   226   young_gen()->space_invariants();

   227   old_gen()->space_invariants();

   229   if (TraceAdaptiveGCBoundary) {

   230     gclog_or_tty->print_cr("After expansion of young gen with boundary move");

   231     if (!PrintHeapAtGC) {

   232       Universe::print_on(gclog_or_tty);

   233     }

   234     gclog_or_tty->print_cr("  PSYoungGen max size: " SIZE_FORMAT "K",

   235       young_gen()->max_size()/K);

   236   }

   238   return result;

   239 }

   241 // Additional space is needed in the old generation.  Try to move the boundary

   242 // up to meet the need.  Moves boundary up only

   243 void AdjoiningGenerations::adjust_boundary_for_old_gen_needs(

   244   size_t desired_free_space) {

   245   assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

   247   // Stress testing.

   248   if (PSAdaptiveSizePolicyResizeVirtualSpaceAlot == 1) {

   249     MutexLocker x(ExpandHeap_lock);

   250     request_old_gen_expansion(virtual_spaces()->alignment() * 3 / 2);

   251   }

   253   // Expand only if the entire generation is already committed.

   254   if (old_gen()->virtual_space()->uncommitted_size() == 0) {

   255     if (old_gen()->free_in_bytes() < desired_free_space) {

   256       MutexLocker x(ExpandHeap_lock);

   257       request_old_gen_expansion(desired_free_space);

   258     }

   259   }

   260 }

   262 // See comment on adjust_boundary_for_old_gen_needss().

   263 // Adjust boundary down only.

   264 void AdjoiningGenerations::adjust_boundary_for_young_gen_needs(size_t eden_size,

   265     size_t survivor_size) {

   267   assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

   269   // Stress testing.

   270   if (PSAdaptiveSizePolicyResizeVirtualSpaceAlot == 0) {

   271     request_young_gen_expansion(virtual_spaces()->alignment() * 3 / 2);

   272     eden_size = young_gen()->eden_space()->capacity_in_bytes();

   273   }

   275   // Expand only if the entire generation is already committed.

   276   if (young_gen()->virtual_space()->uncommitted_size() == 0) {

   277     size_t desired_size = eden_size + 2 * survivor_size;

   278     const size_t committed = young_gen()->virtual_space()->committed_size();

   279     if (desired_size > committed) {

   280       request_young_gen_expansion(desired_size - committed);

   281     }

   282   }

   283 }

Mercurial > jdk8-mips64-public > hotspot / file revision

src/share/vm/gc_implementation/parallelScavenge/adjoiningGenerations.cpp@fb69749583e8

src/share/vm/gc_implementation/parallelScavenge/adjoiningGenerations.cpp