1 /*

     2  * Copyright (c) 2004, 2013, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  *

    23  */

    24 

    25 #include "precompiled.hpp"

    26 #include "gc_implementation/concurrentMarkSweep/cmsAdaptiveSizePolicy.hpp"

    27 #include "gc_implementation/shared/gcStats.hpp"

    28 #include "memory/defNewGeneration.hpp"

    29 #include "memory/genCollectedHeap.hpp"

    30 #include "runtime/thread.hpp"

    31 #ifdef TARGET_OS_FAMILY_linux

    32 # include "os_linux.inline.hpp"

    33 #endif

    34 #ifdef TARGET_OS_FAMILY_solaris

    35 # include "os_solaris.inline.hpp"

    36 #endif

    37 #ifdef TARGET_OS_FAMILY_windows

    38 # include "os_windows.inline.hpp"

    39 #endif

    40 #ifdef TARGET_OS_FAMILY_aix

    41 # include "os_aix.inline.hpp"

    42 #endif

    43 #ifdef TARGET_OS_FAMILY_bsd

    44 # include "os_bsd.inline.hpp"

    45 #endif

    46 elapsedTimer CMSAdaptiveSizePolicy::_concurrent_timer;

    47 elapsedTimer CMSAdaptiveSizePolicy::_STW_timer;

    48 

    49 // Defined if the granularity of the time measurements is potentially too large.

    50 #define CLOCK_GRANULARITY_TOO_LARGE

    51 

    52 CMSAdaptiveSizePolicy::CMSAdaptiveSizePolicy(size_t init_eden_size,

    53                                              size_t init_promo_size,

    54                                              size_t init_survivor_size,

    55                                              double max_gc_minor_pause_sec,

    56                                              double max_gc_pause_sec,

    57                                              uint gc_cost_ratio) :

    58   AdaptiveSizePolicy(init_eden_size,

    59                      init_promo_size,

    60                      init_survivor_size,

    61                      max_gc_pause_sec,

    62                      gc_cost_ratio) {

    63 

    64   clear_internal_time_intervals();

    65 

    66   _processor_count = os::active_processor_count();

    67 

    68   if (CMSConcurrentMTEnabled && (ConcGCThreads > 1)) {

    69     assert(_processor_count > 0, "Processor count is suspect");

    70     _concurrent_processor_count = MIN2((uint) ConcGCThreads,

    71                                        (uint) _processor_count);

    72   } else {

    73     _concurrent_processor_count = 1;

    74   }

    75 

    76   _avg_concurrent_time  = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    77   _avg_concurrent_interval = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    78   _avg_concurrent_gc_cost = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    79 

    80   _avg_initial_pause    = new AdaptivePaddedAverage(AdaptiveTimeWeight,

    81                                                     PausePadding);

    82   _avg_remark_pause     = new AdaptivePaddedAverage(AdaptiveTimeWeight,

    83                                                     PausePadding);

    84 

    85   _avg_cms_STW_time     = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    86   _avg_cms_STW_gc_cost  = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    87 

    88   _avg_cms_free         = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    89   _avg_cms_free_at_sweep = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    90   _avg_cms_promo        = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    91 

    92   // Mark-sweep-compact

    93   _avg_msc_pause        = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    94   _avg_msc_interval     = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    95   _avg_msc_gc_cost      = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    96 

    97   // Mark-sweep

    98   _avg_ms_pause = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

    99   _avg_ms_interval      = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

   100   _avg_ms_gc_cost       = new AdaptiveWeightedAverage(AdaptiveTimeWeight);

   101 

   102   // Variables that estimate pause times as a function of generation

   103   // size.

   104   _remark_pause_old_estimator =

   105     new LinearLeastSquareFit(AdaptiveSizePolicyWeight);

   106   _initial_pause_old_estimator =

   107     new LinearLeastSquareFit(AdaptiveSizePolicyWeight);

   108   _remark_pause_young_estimator =

   109     new LinearLeastSquareFit(AdaptiveSizePolicyWeight);

   110   _initial_pause_young_estimator =

   111     new LinearLeastSquareFit(AdaptiveSizePolicyWeight);

   112 

   113   // Alignment comes from that used in ReservedSpace.

   114   _generation_alignment = os::vm_allocation_granularity();

   115 

   116   // Start the concurrent timer here so that the first

   117   // concurrent_phases_begin() measures a finite mutator

   118   // time.  A finite mutator time is used to determine

   119   // if a concurrent collection has been started.  If this

   120   // proves to be a problem, use some explicit flag to

   121   // signal that a concurrent collection has been started.

   122   _concurrent_timer.start();

   123   _STW_timer.start();

   124 }

   125 

   126 double CMSAdaptiveSizePolicy::concurrent_processor_fraction() {

   127   // For now assume no other daemon threads are taking alway

   128   // cpu's from the application.

   129   return ((double) _concurrent_processor_count / (double) _processor_count);

   130 }

   131 

   132 double CMSAdaptiveSizePolicy::concurrent_collection_cost(

   133                                                   double interval_in_seconds) {

   134   //  When the precleaning and sweeping phases use multiple

   135   // threads, change one_processor_fraction to

   136   // concurrent_processor_fraction().

   137   double one_processor_fraction = 1.0 / ((double) processor_count());

   138   double concurrent_cost =

   139     collection_cost(_latest_cms_concurrent_marking_time_secs,

   140                 interval_in_seconds) * concurrent_processor_fraction() +

   141     collection_cost(_latest_cms_concurrent_precleaning_time_secs,

   142                 interval_in_seconds) * one_processor_fraction +

   143     collection_cost(_latest_cms_concurrent_sweeping_time_secs,

   144                 interval_in_seconds) * one_processor_fraction;

   145   if (PrintAdaptiveSizePolicy && Verbose) {

   146     gclog_or_tty->print_cr(

   147       "\nCMSAdaptiveSizePolicy::scaled_concurrent_collection_cost(%f) "

   148       "_latest_cms_concurrent_marking_cost %f "

   149       "_latest_cms_concurrent_precleaning_cost %f "

   150       "_latest_cms_concurrent_sweeping_cost %f "

   151       "concurrent_processor_fraction %f "

   152       "concurrent_cost %f ",

   153       interval_in_seconds,

   154       collection_cost(_latest_cms_concurrent_marking_time_secs,

   155         interval_in_seconds),

   156       collection_cost(_latest_cms_concurrent_precleaning_time_secs,

   157         interval_in_seconds),

   158       collection_cost(_latest_cms_concurrent_sweeping_time_secs,

   159         interval_in_seconds),

   160       concurrent_processor_fraction(),

   161       concurrent_cost);

   162   }

   163   return concurrent_cost;

   164 }

   165 

   166 double CMSAdaptiveSizePolicy::concurrent_collection_time() {

   167   double latest_cms_sum_concurrent_phases_time_secs =

   168     _latest_cms_concurrent_marking_time_secs +

   169     _latest_cms_concurrent_precleaning_time_secs +

   170     _latest_cms_concurrent_sweeping_time_secs;

   171   return latest_cms_sum_concurrent_phases_time_secs;

   172 }

   173 

   174 double CMSAdaptiveSizePolicy::scaled_concurrent_collection_time() {

   175   //  When the precleaning and sweeping phases use multiple

   176   // threads, change one_processor_fraction to

   177   // concurrent_processor_fraction().

   178   double one_processor_fraction = 1.0 / ((double) processor_count());

   179   double latest_cms_sum_concurrent_phases_time_secs =

   180     _latest_cms_concurrent_marking_time_secs * concurrent_processor_fraction() +

   181     _latest_cms_concurrent_precleaning_time_secs * one_processor_fraction +

   182     _latest_cms_concurrent_sweeping_time_secs * one_processor_fraction ;

   183   if (PrintAdaptiveSizePolicy && Verbose) {

   184     gclog_or_tty->print_cr(

   185       "\nCMSAdaptiveSizePolicy::scaled_concurrent_collection_time "

   186       "_latest_cms_concurrent_marking_time_secs %f "

   187       "_latest_cms_concurrent_precleaning_time_secs %f "

   188       "_latest_cms_concurrent_sweeping_time_secs %f "

   189       "concurrent_processor_fraction %f "

   190       "latest_cms_sum_concurrent_phases_time_secs %f ",

   191       _latest_cms_concurrent_marking_time_secs,

   192       _latest_cms_concurrent_precleaning_time_secs,

   193       _latest_cms_concurrent_sweeping_time_secs,

   194       concurrent_processor_fraction(),

   195       latest_cms_sum_concurrent_phases_time_secs);

   196   }

   197   return latest_cms_sum_concurrent_phases_time_secs;

   198 }

   199 

   200 void CMSAdaptiveSizePolicy::update_minor_pause_old_estimator(

   201     double minor_pause_in_ms) {

   202   // Get the equivalent of the free space

   203   // that is available for promotions in the CMS generation

   204   // and use that to update _minor_pause_old_estimator

   205 

   206   // Don't implement this until it is needed. A warning is

   207   // printed if _minor_pause_old_estimator is used.

   208 }

   209 

   210 void CMSAdaptiveSizePolicy::concurrent_marking_begin() {

   211   if (PrintAdaptiveSizePolicy && Verbose) {

   212     gclog_or_tty->print(" ");

   213     gclog_or_tty->stamp();

   214     gclog_or_tty->print(": concurrent_marking_begin ");

   215   }

   216   //  Update the interval time

   217   _concurrent_timer.stop();

   218   _latest_cms_collection_end_to_collection_start_secs = _concurrent_timer.seconds();

   219   if (PrintAdaptiveSizePolicy && Verbose) {

   220     gclog_or_tty->print_cr("CMSAdaptiveSizePolicy::concurrent_marking_begin: "

   221     "mutator time %f", _latest_cms_collection_end_to_collection_start_secs);

   222   }

   223   _concurrent_timer.reset();

   224   _concurrent_timer.start();

   225 }

   226 

   227 void CMSAdaptiveSizePolicy::concurrent_marking_end() {

   228   if (PrintAdaptiveSizePolicy && Verbose) {

   229     gclog_or_tty->stamp();

   230     gclog_or_tty->print_cr("CMSAdaptiveSizePolicy::concurrent_marking_end()");

   231   }

   232 

   233   _concurrent_timer.stop();

   234   _latest_cms_concurrent_marking_time_secs = _concurrent_timer.seconds();

   235 

   236   if (PrintAdaptiveSizePolicy && Verbose) {

   237     gclog_or_tty->print_cr("\n CMSAdaptiveSizePolicy::concurrent_marking_end"

   238       ":concurrent marking time (s) %f",

   239       _latest_cms_concurrent_marking_time_secs);

   240   }

   241 }

   242 

   243 void CMSAdaptiveSizePolicy::concurrent_precleaning_begin() {

   244   if (PrintAdaptiveSizePolicy && Verbose) {

   245     gclog_or_tty->stamp();

   246     gclog_or_tty->print_cr(

   247       "CMSAdaptiveSizePolicy::concurrent_precleaning_begin()");

   248   }

   249   _concurrent_timer.reset();

   250   _concurrent_timer.start();

   251 }

   252 

   253 

   254 void CMSAdaptiveSizePolicy::concurrent_precleaning_end() {

   255   if (PrintAdaptiveSizePolicy && Verbose) {

   256     gclog_or_tty->stamp();

   257     gclog_or_tty->print_cr("CMSAdaptiveSizePolicy::concurrent_precleaning_end()");

   258   }

   259 

   260   _concurrent_timer.stop();

   261   // May be set again by a second call during the same collection.

   262   _latest_cms_concurrent_precleaning_time_secs = _concurrent_timer.seconds();

   263 

   264   if (PrintAdaptiveSizePolicy && Verbose) {

   265     gclog_or_tty->print_cr("\n CMSAdaptiveSizePolicy::concurrent_precleaning_end"

   266       ":concurrent precleaning time (s) %f",

   267       _latest_cms_concurrent_precleaning_time_secs);

   268   }

   269 }

   270 

   271 void CMSAdaptiveSizePolicy::concurrent_sweeping_begin() {

   272   if (PrintAdaptiveSizePolicy && Verbose) {

   273     gclog_or_tty->stamp();

   274     gclog_or_tty->print_cr(

   275       "CMSAdaptiveSizePolicy::concurrent_sweeping_begin()");

   276   }

   277   _concurrent_timer.reset();

   278   _concurrent_timer.start();

   279 }

   280 

   281 

   282 void CMSAdaptiveSizePolicy::concurrent_sweeping_end() {

   283   if (PrintAdaptiveSizePolicy && Verbose) {

   284     gclog_or_tty->stamp();

   285     gclog_or_tty->print_cr("CMSAdaptiveSizePolicy::concurrent_sweeping_end()");

   286   }

   287 

   288   _concurrent_timer.stop();

   289   _latest_cms_concurrent_sweeping_time_secs = _concurrent_timer.seconds();

   290 

   291   if (PrintAdaptiveSizePolicy && Verbose) {

   292     gclog_or_tty->print_cr("\n CMSAdaptiveSizePolicy::concurrent_sweeping_end"

   293       ":concurrent sweeping time (s) %f",

   294       _latest_cms_concurrent_sweeping_time_secs);

   295   }

   296 }

   297 

   298 void CMSAdaptiveSizePolicy::concurrent_phases_end(GCCause::Cause gc_cause,

   299                                                   size_t cur_eden,

   300                                                   size_t cur_promo) {

   301   if (PrintAdaptiveSizePolicy && Verbose) {

   302     gclog_or_tty->print(" ");

   303     gclog_or_tty->stamp();

   304     gclog_or_tty->print(": concurrent_phases_end ");

   305   }

   306 

   307   // Update the concurrent timer

   308   _concurrent_timer.stop();

   309 

   310   if (gc_cause != GCCause::_java_lang_system_gc ||

   311       UseAdaptiveSizePolicyWithSystemGC) {

   312 

   313     avg_cms_free()->sample(cur_promo);

   314     double latest_cms_sum_concurrent_phases_time_secs =

   315       concurrent_collection_time();

   316 

   317     _avg_concurrent_time->sample(latest_cms_sum_concurrent_phases_time_secs);

   318 

   319     // Cost of collection (unit-less)

   320 

   321     // Total interval for collection.  May not be valid.  Tests

   322     // below determine whether to use this.

   323     //

   324   if (PrintAdaptiveSizePolicy && Verbose) {

   325     gclog_or_tty->print_cr("\nCMSAdaptiveSizePolicy::concurrent_phases_end \n"

   326       "_latest_cms_reset_end_to_initial_mark_start_secs %f \n"

   327       "_latest_cms_initial_mark_start_to_end_time_secs %f \n"

   328       "_latest_cms_remark_start_to_end_time_secs %f \n"

   329       "_latest_cms_concurrent_marking_time_secs %f \n"

   330       "_latest_cms_concurrent_precleaning_time_secs %f \n"

   331       "_latest_cms_concurrent_sweeping_time_secs %f \n"

   332       "latest_cms_sum_concurrent_phases_time_secs %f \n"

   333       "_latest_cms_collection_end_to_collection_start_secs %f \n"

   334       "concurrent_processor_fraction %f",

   335       _latest_cms_reset_end_to_initial_mark_start_secs,

   336       _latest_cms_initial_mark_start_to_end_time_secs,

   337       _latest_cms_remark_start_to_end_time_secs,

   338       _latest_cms_concurrent_marking_time_secs,

   339       _latest_cms_concurrent_precleaning_time_secs,

   340       _latest_cms_concurrent_sweeping_time_secs,

   341       latest_cms_sum_concurrent_phases_time_secs,

   342       _latest_cms_collection_end_to_collection_start_secs,

   343       concurrent_processor_fraction());

   344   }

   345     double interval_in_seconds =

   346       _latest_cms_initial_mark_start_to_end_time_secs +

   347       _latest_cms_remark_start_to_end_time_secs +

   348       latest_cms_sum_concurrent_phases_time_secs +

   349       _latest_cms_collection_end_to_collection_start_secs;

   350     assert(interval_in_seconds >= 0.0,

   351       "Bad interval between cms collections");

   352 

   353     // Sample for performance counter

   354     avg_concurrent_interval()->sample(interval_in_seconds);

   355 

   356     // STW costs (initial and remark pauses)

   357     // Cost of collection (unit-less)

   358     assert(_latest_cms_initial_mark_start_to_end_time_secs >= 0.0,

   359       "Bad initial mark pause");

   360     assert(_latest_cms_remark_start_to_end_time_secs >= 0.0,

   361       "Bad remark pause");

   362     double STW_time_in_seconds =

   363       _latest_cms_initial_mark_start_to_end_time_secs +

   364       _latest_cms_remark_start_to_end_time_secs;

   365     double STW_collection_cost = 0.0;

   366     if (interval_in_seconds > 0.0) {

   367       // cost for the STW phases of the concurrent collection.

   368       STW_collection_cost = STW_time_in_seconds / interval_in_seconds;

   369       avg_cms_STW_gc_cost()->sample(STW_collection_cost);

   370     }

   371     if (PrintAdaptiveSizePolicy && Verbose) {

   372       gclog_or_tty->print("cmsAdaptiveSizePolicy::STW_collection_end: "

   373         "STW gc cost: %f  average: %f", STW_collection_cost,

   374         avg_cms_STW_gc_cost()->average());

   375       gclog_or_tty->print_cr("  STW pause: %f (ms) STW period %f (ms)",

   376         (double) STW_time_in_seconds * MILLIUNITS,

   377         (double) interval_in_seconds * MILLIUNITS);

   378     }

   379 

   380     double concurrent_cost = 0.0;

   381     if (latest_cms_sum_concurrent_phases_time_secs > 0.0) {

   382       concurrent_cost = concurrent_collection_cost(interval_in_seconds);

   383 

   384       avg_concurrent_gc_cost()->sample(concurrent_cost);

   385       // Average this ms cost into all the other types gc costs

   386 

   387       if (PrintAdaptiveSizePolicy && Verbose) {

   388         gclog_or_tty->print("cmsAdaptiveSizePolicy::concurrent_phases_end: "

   389           "concurrent gc cost: %f  average: %f",

   390           concurrent_cost,

   391           _avg_concurrent_gc_cost->average());

   392         gclog_or_tty->print_cr("  concurrent time: %f (ms) cms period %f (ms)"

   393           " processor fraction: %f",

   394           latest_cms_sum_concurrent_phases_time_secs * MILLIUNITS,

   395           interval_in_seconds * MILLIUNITS,

   396           concurrent_processor_fraction());

   397       }

   398     }

   399     double total_collection_cost = STW_collection_cost + concurrent_cost;

   400     avg_major_gc_cost()->sample(total_collection_cost);

   401 

   402     // Gather information for estimating future behavior

   403     double initial_pause_in_ms = _latest_cms_initial_mark_start_to_end_time_secs * MILLIUNITS;

   404     double remark_pause_in_ms = _latest_cms_remark_start_to_end_time_secs * MILLIUNITS;

   405 

   406     double cur_promo_size_in_mbytes = ((double)cur_promo)/((double)M);

   407     initial_pause_old_estimator()->update(cur_promo_size_in_mbytes,

   408       initial_pause_in_ms);

   409     remark_pause_old_estimator()->update(cur_promo_size_in_mbytes,

   410       remark_pause_in_ms);

   411     major_collection_estimator()->update(cur_promo_size_in_mbytes,

   412       total_collection_cost);

   413 

   414     // This estimate uses the average eden size.  It could also

   415     // have used the latest eden size.  Which is better?

   416     double cur_eden_size_in_mbytes = ((double)cur_eden)/((double) M);

   417     initial_pause_young_estimator()->update(cur_eden_size_in_mbytes,

   418       initial_pause_in_ms);

   419     remark_pause_young_estimator()->update(cur_eden_size_in_mbytes,

   420       remark_pause_in_ms);

   421   }

   422 

   423   clear_internal_time_intervals();

   424 

   425   set_first_after_collection();

   426 

   427   // The concurrent phases keeps track of it's own mutator interval

   428   // with this timer.  This allows the stop-the-world phase to

   429   // be included in the mutator time so that the stop-the-world time

   430   // is not double counted.  Reset and start it.

   431   _concurrent_timer.reset();

   432   _concurrent_timer.start();

   433 

   434   // The mutator time between STW phases does not include the

   435   // concurrent collection time.

   436   _STW_timer.reset();

   437   _STW_timer.start();

   438 }

   439 

   440 void CMSAdaptiveSizePolicy::checkpoint_roots_initial_begin() {

   441   //  Update the interval time

   442   _STW_timer.stop();

   443   _latest_cms_reset_end_to_initial_mark_start_secs = _STW_timer.seconds();

   444   // Reset for the initial mark

   445   _STW_timer.reset();

   446   _STW_timer.start();

   447 }

   448 

   449 void CMSAdaptiveSizePolicy::checkpoint_roots_initial_end(

   450     GCCause::Cause gc_cause) {

   451   _STW_timer.stop();

   452 

   453   if (gc_cause != GCCause::_java_lang_system_gc ||

   454       UseAdaptiveSizePolicyWithSystemGC) {

   455     _latest_cms_initial_mark_start_to_end_time_secs = _STW_timer.seconds();

   456     avg_initial_pause()->sample(_latest_cms_initial_mark_start_to_end_time_secs);

   457 

   458     if (PrintAdaptiveSizePolicy && Verbose) {

   459       gclog_or_tty->print(

   460         "cmsAdaptiveSizePolicy::checkpoint_roots_initial_end: "

   461         "initial pause: %f ", _latest_cms_initial_mark_start_to_end_time_secs);

   462     }

   463   }

   464 

   465   _STW_timer.reset();

   466   _STW_timer.start();

   467 }

   468 

   469 void CMSAdaptiveSizePolicy::checkpoint_roots_final_begin() {

   470   _STW_timer.stop();

   471   _latest_cms_initial_mark_end_to_remark_start_secs = _STW_timer.seconds();

   472   // Start accumulating time for the remark in the STW timer.

   473   _STW_timer.reset();

   474   _STW_timer.start();

   475 }

   476 

   477 void CMSAdaptiveSizePolicy::checkpoint_roots_final_end(

   478     GCCause::Cause gc_cause) {

   479   _STW_timer.stop();

   480   if (gc_cause != GCCause::_java_lang_system_gc ||

   481       UseAdaptiveSizePolicyWithSystemGC) {

   482     // Total initial mark pause + remark pause.

   483     _latest_cms_remark_start_to_end_time_secs = _STW_timer.seconds();

   484     double STW_time_in_seconds = _latest_cms_initial_mark_start_to_end_time_secs +

   485       _latest_cms_remark_start_to_end_time_secs;

   486     double STW_time_in_ms = STW_time_in_seconds * MILLIUNITS;

   487 

   488     avg_remark_pause()->sample(_latest_cms_remark_start_to_end_time_secs);

   489 

   490     // Sample total for initial mark + remark

   491     avg_cms_STW_time()->sample(STW_time_in_seconds);

   492 

   493     if (PrintAdaptiveSizePolicy && Verbose) {

   494       gclog_or_tty->print("cmsAdaptiveSizePolicy::checkpoint_roots_final_end: "

   495         "remark pause: %f", _latest_cms_remark_start_to_end_time_secs);

   496     }

   497 

   498   }

   499   // Don't start the STW times here because the concurrent

   500   // sweep and reset has not happened.

   501   //  Keep the old comment above in case I don't understand

   502   // what is going on but now

   503   // Start the STW timer because it is used by ms_collection_begin()

   504   // and ms_collection_end() to get the sweep time if a MS is being

   505   // done in the foreground.

   506   _STW_timer.reset();

   507   _STW_timer.start();

   508 }

   509 

   510 void CMSAdaptiveSizePolicy::msc_collection_begin() {

   511   if (PrintAdaptiveSizePolicy && Verbose) {

   512     gclog_or_tty->print(" ");

   513     gclog_or_tty->stamp();

   514     gclog_or_tty->print(": msc_collection_begin ");

   515   }

   516   _STW_timer.stop();

   517   _latest_cms_msc_end_to_msc_start_time_secs = _STW_timer.seconds();

   518   if (PrintAdaptiveSizePolicy && Verbose) {

   519     gclog_or_tty->print_cr("CMSAdaptiveSizePolicy::msc_collection_begin: "

   520       "mutator time %f",

   521       _latest_cms_msc_end_to_msc_start_time_secs);

   522   }

   523   avg_msc_interval()->sample(_latest_cms_msc_end_to_msc_start_time_secs);

   524   _STW_timer.reset();

   525   _STW_timer.start();

   526 }

   527 

   528 void CMSAdaptiveSizePolicy::msc_collection_end(GCCause::Cause gc_cause) {

   529   if (PrintAdaptiveSizePolicy && Verbose) {

   530     gclog_or_tty->print(" ");

   531     gclog_or_tty->stamp();

   532     gclog_or_tty->print(": msc_collection_end ");

   533   }

   534   _STW_timer.stop();

   535   if (gc_cause != GCCause::_java_lang_system_gc ||

   536         UseAdaptiveSizePolicyWithSystemGC) {

   537     double msc_pause_in_seconds = _STW_timer.seconds();

   538     if ((_latest_cms_msc_end_to_msc_start_time_secs > 0.0) &&

   539         (msc_pause_in_seconds > 0.0)) {

   540       avg_msc_pause()->sample(msc_pause_in_seconds);

   541       double mutator_time_in_seconds = 0.0;

   542       if (_latest_cms_collection_end_to_collection_start_secs == 0.0) {

   543         // This assertion may fail because of time stamp granularity.

   544         // Comment it out and investigate it at a later time.  The large

   545         // time stamp granularity occurs on some older linux systems.

   546 #ifndef CLOCK_GRANULARITY_TOO_LARGE

   547         assert((_latest_cms_concurrent_marking_time_secs == 0.0) &&

   548                (_latest_cms_concurrent_precleaning_time_secs == 0.0) &&

   549                (_latest_cms_concurrent_sweeping_time_secs == 0.0),

   550           "There should not be any concurrent time");

   551 #endif

   552         // A concurrent collection did not start.  Mutator time

   553         // between collections comes from the STW MSC timer.

   554         mutator_time_in_seconds = _latest_cms_msc_end_to_msc_start_time_secs;

   555       } else {

   556         // The concurrent collection did start so count the mutator

   557         // time to the start of the concurrent collection.  In this

   558         // case the _latest_cms_msc_end_to_msc_start_time_secs measures

   559         // the time between the initial mark or remark and the

   560         // start of the MSC.  That has no real meaning.

   561         mutator_time_in_seconds = _latest_cms_collection_end_to_collection_start_secs;

   562       }

   563 

   564       double latest_cms_sum_concurrent_phases_time_secs =

   565         concurrent_collection_time();

   566       double interval_in_seconds =

   567         mutator_time_in_seconds +

   568         _latest_cms_initial_mark_start_to_end_time_secs +

   569         _latest_cms_remark_start_to_end_time_secs +

   570         latest_cms_sum_concurrent_phases_time_secs +

   571         msc_pause_in_seconds;

   572 

   573       if (PrintAdaptiveSizePolicy && Verbose) {

   574         gclog_or_tty->print_cr("  interval_in_seconds %f \n"

   575           "     mutator_time_in_seconds %f \n"

   576           "     _latest_cms_initial_mark_start_to_end_time_secs %f\n"

   577           "     _latest_cms_remark_start_to_end_time_secs %f\n"

   578           "     latest_cms_sum_concurrent_phases_time_secs %f\n"

   579           "     msc_pause_in_seconds %f\n",

   580           interval_in_seconds,

   581           mutator_time_in_seconds,

   582           _latest_cms_initial_mark_start_to_end_time_secs,

   583           _latest_cms_remark_start_to_end_time_secs,

   584           latest_cms_sum_concurrent_phases_time_secs,

   585           msc_pause_in_seconds);

   586       }

   587 

   588       // The concurrent cost is wasted cost but it should be

   589       // included.

   590       double concurrent_cost = concurrent_collection_cost(interval_in_seconds);

   591 

   592       // Initial mark and remark, also wasted.

   593       double STW_time_in_seconds = _latest_cms_initial_mark_start_to_end_time_secs +

   594         _latest_cms_remark_start_to_end_time_secs;

   595       double STW_collection_cost =

   596         collection_cost(STW_time_in_seconds, interval_in_seconds) +

   597         concurrent_cost;

   598 

   599       if (PrintAdaptiveSizePolicy && Verbose) {

   600         gclog_or_tty->print_cr(" msc_collection_end:\n"

   601           "_latest_cms_collection_end_to_collection_start_secs %f\n"

   602           "_latest_cms_msc_end_to_msc_start_time_secs %f\n"

   603           "_latest_cms_initial_mark_start_to_end_time_secs %f\n"

   604           "_latest_cms_remark_start_to_end_time_secs %f\n"

   605           "latest_cms_sum_concurrent_phases_time_secs %f\n",

   606           _latest_cms_collection_end_to_collection_start_secs,

   607           _latest_cms_msc_end_to_msc_start_time_secs,

   608           _latest_cms_initial_mark_start_to_end_time_secs,

   609           _latest_cms_remark_start_to_end_time_secs,

   610           latest_cms_sum_concurrent_phases_time_secs);

   611 

   612         gclog_or_tty->print_cr(" msc_collection_end: \n"

   613           "latest_cms_sum_concurrent_phases_time_secs %f\n"

   614           "STW_time_in_seconds %f\n"

   615           "msc_pause_in_seconds %f\n",

   616           latest_cms_sum_concurrent_phases_time_secs,

   617           STW_time_in_seconds,

   618           msc_pause_in_seconds);

   619       }

   620 

   621       double cost = concurrent_cost + STW_collection_cost +

   622         collection_cost(msc_pause_in_seconds, interval_in_seconds);

   623 

   624       _avg_msc_gc_cost->sample(cost);

   625 

   626       // Average this ms cost into all the other types gc costs

   627       avg_major_gc_cost()->sample(cost);

   628 

   629       // Sample for performance counter

   630       _avg_msc_interval->sample(interval_in_seconds);

   631       if (PrintAdaptiveSizePolicy && Verbose) {

   632         gclog_or_tty->print("cmsAdaptiveSizePolicy::msc_collection_end: "

   633           "MSC gc cost: %f  average: %f", cost,

   634           _avg_msc_gc_cost->average());

   635 

   636         double msc_pause_in_ms = msc_pause_in_seconds * MILLIUNITS;

   637         gclog_or_tty->print_cr("  MSC pause: %f (ms) MSC period %f (ms)",

   638           msc_pause_in_ms, (double) interval_in_seconds * MILLIUNITS);

   639       }

   640     }

   641   }

   642 

   643   clear_internal_time_intervals();

   644 

   645   // Can this call be put into the epilogue?

   646   set_first_after_collection();

   647 

   648   // The concurrent phases keeps track of it's own mutator interval

   649   // with this timer.  This allows the stop-the-world phase to

   650   // be included in the mutator time so that the stop-the-world time

   651   // is not double counted.  Reset and start it.

   652   _concurrent_timer.stop();

   653   _concurrent_timer.reset();

   654   _concurrent_timer.start();

   655 

   656   _STW_timer.reset();

   657   _STW_timer.start();

   658 }

   659 

   660 void CMSAdaptiveSizePolicy::ms_collection_begin() {

   661   if (PrintAdaptiveSizePolicy && Verbose) {

   662     gclog_or_tty->print(" ");

   663     gclog_or_tty->stamp();

   664     gclog_or_tty->print(": ms_collection_begin ");

   665   }

   666   _STW_timer.stop();

   667   _latest_cms_ms_end_to_ms_start = _STW_timer.seconds();

   668   if (PrintAdaptiveSizePolicy && Verbose) {

   669     gclog_or_tty->print_cr("CMSAdaptiveSizePolicy::ms_collection_begin: "

   670       "mutator time %f",

   671       _latest_cms_ms_end_to_ms_start);

   672   }

   673   avg_ms_interval()->sample(_STW_timer.seconds());

   674   _STW_timer.reset();

   675   _STW_timer.start();

   676 }

   677 

   678 void CMSAdaptiveSizePolicy::ms_collection_end(GCCause::Cause gc_cause) {

   679   if (PrintAdaptiveSizePolicy && Verbose) {

   680     gclog_or_tty->print(" ");

   681     gclog_or_tty->stamp();

   682     gclog_or_tty->print(": ms_collection_end ");

   683   }

   684   _STW_timer.stop();

   685   if (gc_cause != GCCause::_java_lang_system_gc ||

   686         UseAdaptiveSizePolicyWithSystemGC) {

   687     // The MS collection is a foreground collection that does all

   688     // the parts of a mostly concurrent collection.

   689     //

   690     // For this collection include the cost of the

   691     //  initial mark

   692     //  remark

   693     //  all concurrent time (scaled down by the

   694     //    concurrent_processor_fraction).  Some

   695     //    may be zero if the baton was passed before

   696     //    it was reached.

   697     //    concurrent marking

   698     //    sweeping

   699     //    resetting

   700     //  STW after baton was passed (STW_in_foreground_in_seconds)

   701     double STW_in_foreground_in_seconds = _STW_timer.seconds();

   702 

   703     double latest_cms_sum_concurrent_phases_time_secs =

   704       concurrent_collection_time();

   705     if (PrintAdaptiveSizePolicy && Verbose) {

   706       gclog_or_tty->print_cr("\nCMSAdaptiveSizePolicy::ms_collection_end "

   707         "STW_in_foreground_in_seconds %f "

   708         "_latest_cms_initial_mark_start_to_end_time_secs %f "

   709         "_latest_cms_remark_start_to_end_time_secs %f "

   710         "latest_cms_sum_concurrent_phases_time_secs %f "

   711         "_latest_cms_ms_marking_start_to_end_time_secs %f "

   712         "_latest_cms_ms_end_to_ms_start %f",

   713         STW_in_foreground_in_seconds,

   714         _latest_cms_initial_mark_start_to_end_time_secs,

   715         _latest_cms_remark_start_to_end_time_secs,

   716         latest_cms_sum_concurrent_phases_time_secs,

   717         _latest_cms_ms_marking_start_to_end_time_secs,

   718         _latest_cms_ms_end_to_ms_start);

   719     }

   720 

   721     double STW_marking_in_seconds = _latest_cms_initial_mark_start_to_end_time_secs +

   722       _latest_cms_remark_start_to_end_time_secs;

   723 #ifndef CLOCK_GRANULARITY_TOO_LARGE

   724     assert(_latest_cms_ms_marking_start_to_end_time_secs == 0.0 ||

   725            latest_cms_sum_concurrent_phases_time_secs == 0.0,

   726            "marking done twice?");

   727 #endif

   728     double ms_time_in_seconds = STW_marking_in_seconds +

   729       STW_in_foreground_in_seconds +

   730       _latest_cms_ms_marking_start_to_end_time_secs +

   731       scaled_concurrent_collection_time();

   732     avg_ms_pause()->sample(ms_time_in_seconds);

   733     // Use the STW costs from the initial mark and remark plus

   734     // the cost of the concurrent phase to calculate a

   735     // collection cost.

   736     double cost = 0.0;

   737     if ((_latest_cms_ms_end_to_ms_start > 0.0) &&

   738         (ms_time_in_seconds > 0.0)) {

   739       double interval_in_seconds =

   740         _latest_cms_ms_end_to_ms_start + ms_time_in_seconds;

   741 

   742       if (PrintAdaptiveSizePolicy && Verbose) {

   743         gclog_or_tty->print_cr("\n ms_time_in_seconds  %f  "

   744           "latest_cms_sum_concurrent_phases_time_secs %f  "

   745           "interval_in_seconds %f",

   746           ms_time_in_seconds,

   747           latest_cms_sum_concurrent_phases_time_secs,

   748           interval_in_seconds);

   749       }

   750 

   751       cost = collection_cost(ms_time_in_seconds, interval_in_seconds);

   752 

   753       _avg_ms_gc_cost->sample(cost);

   754       // Average this ms cost into all the other types gc costs

   755       avg_major_gc_cost()->sample(cost);

   756 

   757       // Sample for performance counter

   758       _avg_ms_interval->sample(interval_in_seconds);

   759     }

   760     if (PrintAdaptiveSizePolicy && Verbose) {

   761       gclog_or_tty->print("cmsAdaptiveSizePolicy::ms_collection_end: "

   762         "MS gc cost: %f  average: %f", cost, _avg_ms_gc_cost->average());

   763 

   764       double ms_time_in_ms = ms_time_in_seconds * MILLIUNITS;

   765       gclog_or_tty->print_cr("  MS pause: %f (ms) MS period %f (ms)",

   766         ms_time_in_ms,

   767         _latest_cms_ms_end_to_ms_start * MILLIUNITS);

   768     }

   769   }

   770 

   771   // Consider putting this code (here to end) into a

   772   // method for convenience.

   773   clear_internal_time_intervals();

   774 

   775   set_first_after_collection();

   776 

   777   // The concurrent phases keeps track of it's own mutator interval

   778   // with this timer.  This allows the stop-the-world phase to

   779   // be included in the mutator time so that the stop-the-world time

   780   // is not double counted.  Reset and start it.

   781   _concurrent_timer.stop();

   782   _concurrent_timer.reset();

   783   _concurrent_timer.start();

   784 

   785   _STW_timer.reset();

   786   _STW_timer.start();

   787 }

   788 

   789 void CMSAdaptiveSizePolicy::clear_internal_time_intervals() {

   790   _latest_cms_reset_end_to_initial_mark_start_secs = 0.0;

   791   _latest_cms_initial_mark_end_to_remark_start_secs = 0.0;

   792   _latest_cms_collection_end_to_collection_start_secs = 0.0;

   793   _latest_cms_concurrent_marking_time_secs = 0.0;

   794   _latest_cms_concurrent_precleaning_time_secs = 0.0;

   795   _latest_cms_concurrent_sweeping_time_secs = 0.0;

   796   _latest_cms_msc_end_to_msc_start_time_secs = 0.0;

   797   _latest_cms_ms_end_to_ms_start = 0.0;

   798   _latest_cms_remark_start_to_end_time_secs = 0.0;

   799   _latest_cms_initial_mark_start_to_end_time_secs = 0.0;

   800   _latest_cms_ms_marking_start_to_end_time_secs = 0.0;

   801 }

   802 

   803 void CMSAdaptiveSizePolicy::clear_generation_free_space_flags() {

   804   AdaptiveSizePolicy::clear_generation_free_space_flags();

   805 

   806   set_change_young_gen_for_maj_pauses(0);

   807 }

   808 

   809 void CMSAdaptiveSizePolicy::concurrent_phases_resume() {

   810   if (PrintAdaptiveSizePolicy && Verbose) {

   811     gclog_or_tty->stamp();

   812     gclog_or_tty->print_cr("CMSAdaptiveSizePolicy::concurrent_phases_resume()");

   813   }

   814   _concurrent_timer.start();

   815 }

   816 

   817 double CMSAdaptiveSizePolicy::time_since_major_gc() const {

   818   _concurrent_timer.stop();

   819   double time_since_cms_gc = _concurrent_timer.seconds();

   820   _concurrent_timer.start();

   821   _STW_timer.stop();

   822   double time_since_STW_gc = _STW_timer.seconds();

   823   _STW_timer.start();

   824 

   825   return MIN2(time_since_cms_gc, time_since_STW_gc);

   826 }

   827 

   828 double CMSAdaptiveSizePolicy::major_gc_interval_average_for_decay() const {

   829   double cms_interval = _avg_concurrent_interval->average();

   830   double msc_interval = _avg_msc_interval->average();

   831   double ms_interval = _avg_ms_interval->average();

   832 

   833   return MAX3(cms_interval, msc_interval, ms_interval);

   834 }

   835 

   836 double CMSAdaptiveSizePolicy::cms_gc_cost() const {

   837   return avg_major_gc_cost()->average();

   838 }

   839 

   840 void CMSAdaptiveSizePolicy::ms_collection_marking_begin() {

   841   _STW_timer.stop();

   842   // Start accumulating time for the marking in the STW timer.

   843   _STW_timer.reset();

   844   _STW_timer.start();

   845 }

   846 

   847 void CMSAdaptiveSizePolicy::ms_collection_marking_end(

   848     GCCause::Cause gc_cause) {

   849   _STW_timer.stop();

   850   if (gc_cause != GCCause::_java_lang_system_gc ||

   851       UseAdaptiveSizePolicyWithSystemGC) {

   852     _latest_cms_ms_marking_start_to_end_time_secs = _STW_timer.seconds();

   853     if (PrintAdaptiveSizePolicy && Verbose) {

   854       gclog_or_tty->print_cr("CMSAdaptiveSizePolicy::"

   855         "msc_collection_marking_end: mutator time %f",

   856         _latest_cms_ms_marking_start_to_end_time_secs);

   857     }

   858   }

   859   _STW_timer.reset();

   860   _STW_timer.start();

   861 }

   862 

   863 double CMSAdaptiveSizePolicy::gc_cost() const {

   864   double cms_gen_cost = cms_gc_cost();

   865   double result =  MIN2(1.0, minor_gc_cost() + cms_gen_cost);

   866   assert(result >= 0.0, "Both minor and major costs are non-negative");

   867   return result;

   868 }

   869 

   870 // Cost of collection (unit-less)

   871 double CMSAdaptiveSizePolicy::collection_cost(double pause_in_seconds,

   872                                               double interval_in_seconds) {

   873   // Cost of collection (unit-less)

   874   double cost = 0.0;

   875   if ((interval_in_seconds > 0.0) &&

   876       (pause_in_seconds > 0.0)) {

   877     cost =

   878       pause_in_seconds / interval_in_seconds;

   879   }

   880   return cost;

   881 }

   882 

   883 size_t CMSAdaptiveSizePolicy::adjust_eden_for_pause_time(size_t cur_eden) {

   884   size_t change = 0;

   885   size_t desired_eden = cur_eden;

   886 

   887   // reduce eden size

   888   change = eden_decrement_aligned_down(cur_eden);

   889   desired_eden = cur_eden - change;

   890 

   891   if (PrintAdaptiveSizePolicy && Verbose) {

   892     gclog_or_tty->print_cr(

   893       "CMSAdaptiveSizePolicy::adjust_eden_for_pause_time "

   894       "adjusting eden for pause time. "

   895       " starting eden size " SIZE_FORMAT

   896       " reduced eden size " SIZE_FORMAT

   897       " eden delta " SIZE_FORMAT,

   898       cur_eden, desired_eden, change);

   899   }

   900 

   901   return desired_eden;

   902 }

   903 

   904 size_t CMSAdaptiveSizePolicy::adjust_eden_for_throughput(size_t cur_eden) {

   905 

   906   size_t desired_eden = cur_eden;

   907 

   908   set_change_young_gen_for_throughput(increase_young_gen_for_througput_true);

   909 

   910   size_t change = eden_increment_aligned_up(cur_eden);

   911   size_t scaled_change = scale_by_gen_gc_cost(change, minor_gc_cost());

   912 

   913   if (cur_eden + scaled_change > cur_eden) {

   914     desired_eden = cur_eden + scaled_change;

   915   }

   916 

   917   _young_gen_change_for_minor_throughput++;

   918 

   919   if (PrintAdaptiveSizePolicy && Verbose) {

   920     gclog_or_tty->print_cr(

   921       "CMSAdaptiveSizePolicy::adjust_eden_for_throughput "

   922       "adjusting eden for throughput. "

   923       " starting eden size " SIZE_FORMAT

   924       " increased eden size " SIZE_FORMAT

   925       " eden delta " SIZE_FORMAT,

   926       cur_eden, desired_eden, scaled_change);

   927   }

   928 

   929   return desired_eden;

   930 }

   931 

   932 size_t CMSAdaptiveSizePolicy::adjust_eden_for_footprint(size_t cur_eden) {

   933 

   934   set_decrease_for_footprint(decrease_young_gen_for_footprint_true);

   935 

   936   size_t change = eden_decrement(cur_eden);

   937   size_t desired_eden_size = cur_eden - change;

   938 

   939   if (PrintAdaptiveSizePolicy && Verbose) {

   940     gclog_or_tty->print_cr(

   941       "CMSAdaptiveSizePolicy::adjust_eden_for_footprint "

   942       "adjusting eden for footprint. "

   943       " starting eden size " SIZE_FORMAT

   944       " reduced eden size " SIZE_FORMAT

   945       " eden delta " SIZE_FORMAT,

   946       cur_eden, desired_eden_size, change);

   947   }

   948   return desired_eden_size;

   949 }

   950 

   951 // The eden and promo versions should be combined if possible.

   952 // They are the same except that the sizes of the decrement

   953 // and increment are different for eden and promo.

   954 size_t CMSAdaptiveSizePolicy::eden_decrement_aligned_down(size_t cur_eden) {

   955   size_t delta = eden_decrement(cur_eden);

   956   return align_size_down(delta, generation_alignment());

   957 }

   958 

   959 size_t CMSAdaptiveSizePolicy::eden_increment_aligned_up(size_t cur_eden) {

   960   size_t delta = eden_increment(cur_eden);

   961   return align_size_up(delta, generation_alignment());

   962 }

   963 

   964 size_t CMSAdaptiveSizePolicy::promo_decrement_aligned_down(size_t cur_promo) {

   965   size_t delta = promo_decrement(cur_promo);

   966   return align_size_down(delta, generation_alignment());

   967 }

   968 

   969 size_t CMSAdaptiveSizePolicy::promo_increment_aligned_up(size_t cur_promo) {

   970   size_t delta = promo_increment(cur_promo);

   971   return align_size_up(delta, generation_alignment());

   972 }

   973 

   974 

   975 void CMSAdaptiveSizePolicy::compute_eden_space_size(size_t cur_eden,

   976                                                     size_t max_eden_size)

   977 {

   978   size_t desired_eden_size = cur_eden;

   979   size_t eden_limit = max_eden_size;

   980 

   981   // Printout input

   982   if (PrintGC && PrintAdaptiveSizePolicy) {

   983     gclog_or_tty->print_cr(

   984       "CMSAdaptiveSizePolicy::compute_eden_space_size: "

   985       "cur_eden " SIZE_FORMAT,

   986       cur_eden);

   987   }

   988 

   989   // Used for diagnostics

   990   clear_generation_free_space_flags();

   991 

   992   if (_avg_minor_pause->padded_average() > gc_pause_goal_sec()) {

   993     if (minor_pause_young_estimator()->decrement_will_decrease()) {

   994       // If the minor pause is too long, shrink the young gen.

   995       set_change_young_gen_for_min_pauses(

   996         decrease_young_gen_for_min_pauses_true);

   997       desired_eden_size = adjust_eden_for_pause_time(desired_eden_size);

   998     }

   999   } else if ((avg_remark_pause()->padded_average() > gc_pause_goal_sec()) ||

  1000              (avg_initial_pause()->padded_average() > gc_pause_goal_sec())) {

  1001     // The remark or initial pauses are not meeting the goal.  Should

  1002     // the generation be shrunk?

  1003     if (get_and_clear_first_after_collection() &&

  1004         ((avg_remark_pause()->padded_average() > gc_pause_goal_sec() &&

  1005           remark_pause_young_estimator()->decrement_will_decrease()) ||

  1006          (avg_initial_pause()->padded_average() > gc_pause_goal_sec() &&

  1007           initial_pause_young_estimator()->decrement_will_decrease()))) {

  1008 

  1009        set_change_young_gen_for_maj_pauses(

  1010          decrease_young_gen_for_maj_pauses_true);

  1011 

  1012       // If the remark or initial pause is too long and this is the

  1013       // first young gen collection after a cms collection, shrink

  1014       // the young gen.

  1015       desired_eden_size = adjust_eden_for_pause_time(desired_eden_size);

  1016     }

  1017     // If not the first young gen collection after a cms collection,

  1018     // don't do anything.  In this case an adjustment has already

  1019     // been made and the results of the adjustment has not yet been

  1020     // measured.

  1021   } else if ((minor_gc_cost() >= 0.0) &&

  1022              (adjusted_mutator_cost() < _throughput_goal)) {

  1023     desired_eden_size = adjust_eden_for_throughput(desired_eden_size);

  1024   } else {

  1025     desired_eden_size = adjust_eden_for_footprint(desired_eden_size);

  1026   }

  1027 

  1028   if (PrintGC && PrintAdaptiveSizePolicy) {

  1029     gclog_or_tty->print_cr(

  1030       "CMSAdaptiveSizePolicy::compute_eden_space_size limits:"

  1031       " desired_eden_size: " SIZE_FORMAT

  1032       " old_eden_size: " SIZE_FORMAT,

  1033       desired_eden_size, cur_eden);

  1034   }

  1035 

  1036   set_eden_size(desired_eden_size);

  1037 }

  1038 

  1039 size_t CMSAdaptiveSizePolicy::adjust_promo_for_pause_time(size_t cur_promo) {

  1040   size_t change = 0;

  1041   size_t desired_promo = cur_promo;

  1042   // Move this test up to caller like the adjust_eden_for_pause_time()

  1043   // call.

  1044   if ((AdaptiveSizePausePolicy == 0) &&

  1045       ((avg_remark_pause()->padded_average() > gc_pause_goal_sec()) ||

  1046       (avg_initial_pause()->padded_average() > gc_pause_goal_sec()))) {

  1047     set_change_old_gen_for_maj_pauses(decrease_old_gen_for_maj_pauses_true);

  1048     change = promo_decrement_aligned_down(cur_promo);

  1049     desired_promo = cur_promo - change;

  1050   } else if ((AdaptiveSizePausePolicy > 0) &&

  1051       (((avg_remark_pause()->padded_average() > gc_pause_goal_sec()) &&

  1052        remark_pause_old_estimator()->decrement_will_decrease()) ||

  1053       ((avg_initial_pause()->padded_average() > gc_pause_goal_sec()) &&

  1054        initial_pause_old_estimator()->decrement_will_decrease()))) {

  1055     set_change_old_gen_for_maj_pauses(decrease_old_gen_for_maj_pauses_true);

  1056     change = promo_decrement_aligned_down(cur_promo);

  1057     desired_promo = cur_promo - change;

  1058   }

  1059 

  1060   if ((change != 0) &&PrintAdaptiveSizePolicy && Verbose) {

  1061     gclog_or_tty->print_cr(

  1062       "CMSAdaptiveSizePolicy::adjust_promo_for_pause_time "

  1063       "adjusting promo for pause time. "

  1064       " starting promo size " SIZE_FORMAT

  1065       " reduced promo size " SIZE_FORMAT

  1066       " promo delta " SIZE_FORMAT,

  1067       cur_promo, desired_promo, change);

  1068   }

  1069 

  1070   return desired_promo;

  1071 }

  1072 

  1073 // Try to share this with PS.

  1074 size_t CMSAdaptiveSizePolicy::scale_by_gen_gc_cost(size_t base_change,

  1075                                                   double gen_gc_cost) {

  1076 

  1077   // Calculate the change to use for the tenured gen.

  1078   size_t scaled_change = 0;

  1079   // Can the increment to the generation be scaled?

  1080   if (gc_cost() >= 0.0 && gen_gc_cost >= 0.0) {

  1081     double scale_by_ratio = gen_gc_cost / gc_cost();

  1082     scaled_change =

  1083       (size_t) (scale_by_ratio * (double) base_change);

  1084     if (PrintAdaptiveSizePolicy && Verbose) {

  1085       gclog_or_tty->print_cr(

  1086         "Scaled tenured increment: " SIZE_FORMAT " by %f down to "

  1087           SIZE_FORMAT,

  1088         base_change, scale_by_ratio, scaled_change);

  1089     }

  1090   } else if (gen_gc_cost >= 0.0) {

  1091     // Scaling is not going to work.  If the major gc time is the

  1092     // larger than the other GC costs, give it a full increment.

  1093     if (gen_gc_cost >= (gc_cost() - gen_gc_cost)) {

  1094       scaled_change = base_change;

  1095     }

  1096   } else {

  1097     // Don't expect to get here but it's ok if it does

  1098     // in the product build since the delta will be 0

  1099     // and nothing will change.

  1100     assert(false, "Unexpected value for gc costs");

  1101   }

  1102 

  1103   return scaled_change;

  1104 }

  1105 

  1106 size_t CMSAdaptiveSizePolicy::adjust_promo_for_throughput(size_t cur_promo) {

  1107 

  1108   size_t desired_promo = cur_promo;

  1109 

  1110   set_change_old_gen_for_throughput(increase_old_gen_for_throughput_true);

  1111 

  1112   size_t change = promo_increment_aligned_up(cur_promo);

  1113   size_t scaled_change = scale_by_gen_gc_cost(change, major_gc_cost());

  1114 

  1115   if (cur_promo + scaled_change > cur_promo) {

  1116     desired_promo = cur_promo + scaled_change;

  1117   }

  1118 

  1119   _old_gen_change_for_major_throughput++;

  1120 

  1121   if (PrintAdaptiveSizePolicy && Verbose) {

  1122     gclog_or_tty->print_cr(

  1123       "CMSAdaptiveSizePolicy::adjust_promo_for_throughput "

  1124       "adjusting promo for throughput. "

  1125       " starting promo size " SIZE_FORMAT

  1126       " increased promo size " SIZE_FORMAT

  1127       " promo delta " SIZE_FORMAT,

  1128       cur_promo, desired_promo, scaled_change);

  1129   }

  1130 

  1131   return desired_promo;

  1132 }

  1133