--- old/src/share/vm/gc_implementation/parallelScavenge/psAdaptiveSizePolicy.cpp 2013-05-06 14:07:01.000000000 -0700 +++ new/src/share/vm/gc_implementation/parallelScavenge/psAdaptiveSizePolicy.cpp 2013-05-06 14:07:01.000000000 -0700 @@ -201,19 +201,31 @@ size_t cur_eden, size_t max_old_gen_size, size_t max_eden_size, - bool is_full_gc, - GCCause::Cause gc_cause, - CollectorPolicy* collector_policy) { + bool is_full_gc) { + compute_eden_space_size(young_live, + eden_live, + cur_eden, + max_eden_size, + is_full_gc); + + compute_old_gen_free_space(old_live, + cur_eden, + max_old_gen_size, + is_full_gc); +} + +void PSAdaptiveSizePolicy::compute_eden_space_size( + size_t young_live, + size_t eden_live, + size_t cur_eden, + size_t max_eden_size, + bool is_full_gc) { // Update statistics // Time statistics are updated as we go, update footprint stats here _avg_base_footprint->sample(BaseFootPrintEstimate); avg_young_live()->sample(young_live); avg_eden_live()->sample(eden_live); - if (is_full_gc) { - // old_live is only accurate after a full gc - avg_old_live()->sample(old_live); - } // This code used to return if the policy was not ready , i.e., // policy_is_ready() returning false. The intent was that @@ -242,22 +254,11 @@ // some case but is dangerous. size_t desired_eden_size = cur_eden; -#ifdef ASSERT - size_t original_promo_size = desired_promo_size; - size_t original_eden_size = desired_eden_size; -#endif - // Cache some values. There's a bit of work getting these, so // we might save a little time. const double major_cost = major_gc_cost(); const double minor_cost = minor_gc_cost(); - // Used for diagnostics - clear_generation_free_space_flags(); - - // Limits on our growth - size_t promo_limit = (size_t)(max_old_gen_size - avg_old_live()->average()); - // This method sets the desired eden size. That plus the // desired survivor space sizes sets the desired young generation // size. This methods does not know what the desired survivor @@ -268,10 +269,6 @@ // subtracted out. size_t eden_limit = max_eden_size; - // But don't force a promo size below the current promo size. Otherwise, - // the promo size will shrink for no good reason. - promo_limit = MAX2(promo_limit, _promo_size); - const double gc_cost_limit = GCTimeLimit/100.0; // Which way should we go? @@ -286,7 +283,7 @@ // adjust down the total heap size. Adjust down the larger of the // generations. - // Add some checks for a threshhold for a change. For example, + // Add some checks for a threshold for a change. For example, // a change less than the necessary alignment is probably not worth // attempting. @@ -298,11 +295,11 @@ // // Make changes only to affect one of the pauses (the larger) // at a time. - adjust_for_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); + adjust_eden_for_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); } else if (_avg_minor_pause->padded_average() > gc_minor_pause_goal_sec()) { // Adjust only for the minor pause time goal - adjust_for_minor_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); + adjust_eden_for_minor_pause_time(is_full_gc, &desired_eden_size); } else if(adjusted_mutator_cost() < _throughput_goal) { // This branch used to require that (mutator_cost() > 0.0 in 1.4.2. @@ -316,7 +313,7 @@ assert(major_cost >= 0.0, "major cost is < 0.0"); assert(minor_cost >= 0.0, "minor cost is < 0.0"); // Try to reduce the GC times. - adjust_for_throughput(is_full_gc, &desired_promo_size, &desired_eden_size); + adjust_eden_for_throughput(is_full_gc, &desired_eden_size); } else { @@ -328,35 +325,16 @@ avg_major_gc_cost()->average() >= 0.0 && avg_minor_gc_cost()->average() >= 0.0) { size_t desired_sum = desired_eden_size + desired_promo_size; - desired_eden_size = adjust_eden_for_footprint(desired_eden_size, - desired_sum); - if (is_full_gc) { - set_decide_at_full_gc(decide_at_full_gc_true); - desired_promo_size = adjust_promo_for_footprint(desired_promo_size, - desired_sum); - } + desired_eden_size = adjust_eden_for_footprint(desired_eden_size, desired_sum); } } // Note we make the same tests as in the code block below; the code // seems a little easier to read with the printing in another block. if (PrintAdaptiveSizePolicy) { - if (desired_promo_size > promo_limit) { - // "free_in_old_gen" was the original value for used for promo_limit - size_t free_in_old_gen = (size_t)(max_old_gen_size - avg_old_live()->average()); - gclog_or_tty->print_cr( - "PSAdaptiveSizePolicy::compute_generation_free_space limits:" - " desired_promo_size: " SIZE_FORMAT - " promo_limit: " SIZE_FORMAT - " free_in_old_gen: " SIZE_FORMAT - " max_old_gen_size: " SIZE_FORMAT - " avg_old_live: " SIZE_FORMAT, - desired_promo_size, promo_limit, free_in_old_gen, - max_old_gen_size, (size_t) avg_old_live()->average()); - } if (desired_eden_size > eden_limit) { gclog_or_tty->print_cr( - "AdaptiveSizePolicy::compute_generation_free_space limits:" + "PSAdaptiveSizePolicy::compute_eden_space_size limits:" " desired_eden_size: " SIZE_FORMAT " old_eden_size: " SIZE_FORMAT " eden_limit: " SIZE_FORMAT @@ -368,7 +346,7 @@ } if (gc_cost() > gc_cost_limit) { gclog_or_tty->print_cr( - "AdaptiveSizePolicy::compute_generation_free_space: gc time limit" + "PSAdaptiveSizePolicy::compute_eden_space_size: gc time limit" " gc_cost: %f " " GCTimeLimit: %d", gc_cost(), GCTimeLimit); @@ -379,27 +357,8 @@ const size_t alignment = _intra_generation_alignment; desired_eden_size = align_size_up(desired_eden_size, alignment); desired_eden_size = MAX2(desired_eden_size, alignment); - desired_promo_size = align_size_up(desired_promo_size, alignment); - desired_promo_size = MAX2(desired_promo_size, alignment); eden_limit = align_size_down(eden_limit, alignment); - promo_limit = align_size_down(promo_limit, alignment); - - // Is too much time being spent in GC? - // Is the heap trying to grow beyond it's limits? - - const size_t free_in_old_gen = - (size_t)(max_old_gen_size - avg_old_live()->average()); - if (desired_promo_size > free_in_old_gen && desired_eden_size > eden_limit) { - check_gc_overhead_limit(young_live, - eden_live, - max_old_gen_size, - max_eden_size, - is_full_gc, - gc_cause, - collector_policy); - } - // And one last limit check, now that we've aligned things. if (desired_eden_size > eden_limit) { @@ -410,13 +369,11 @@ // into the old gen. desired_eden_size = MAX2(eden_limit, cur_eden); } - desired_promo_size = MIN2(desired_promo_size, promo_limit); - if (PrintAdaptiveSizePolicy) { // Timing stats gclog_or_tty->print( - "PSAdaptiveSizePolicy::compute_generation_free_space: costs" + "PSAdaptiveSizePolicy::compute_eden_space_size: costs" " minor_time: %f" " major_cost: %f" " mutator_cost: %f" @@ -453,20 +410,215 @@ } // And finally, our old and new sizes. - gclog_or_tty->print(" old_promo_size: " SIZE_FORMAT - " old_eden_size: " SIZE_FORMAT - " desired_promo_size: " SIZE_FORMAT + gclog_or_tty->print(" old_eden_size: " SIZE_FORMAT " desired_eden_size: " SIZE_FORMAT, - _promo_size, _eden_size, - desired_promo_size, desired_eden_size); + _eden_size, desired_eden_size); gclog_or_tty->cr(); } - decay_supplemental_growth(is_full_gc); + set_eden_size(desired_eden_size); +} + +void PSAdaptiveSizePolicy::compute_old_gen_free_space( + size_t old_live, + size_t cur_eden, + size_t max_old_gen_size, + bool is_full_gc) { + + // Update statistics + // Time statistics are updated as we go, update footprint stats here + if (is_full_gc) { + // old_live is only accurate after a full gc + avg_old_live()->sample(old_live); + } + + // This code used to return if the policy was not ready , i.e., + // policy_is_ready() returning false. The intent was that + // decisions below needed major collection times and so could + // not be made before two major collections. A consequence was + // adjustments to the young generation were not done until after + // two major collections even if the minor collections times + // exceeded the requested goals. Now let the young generation + // adjust for the minor collection times. Major collection times + // will be zero for the first collection and will naturally be + // ignored. Tenured generation adjustments are only made at the + // full collections so until the second major collection has + // been reached, no tenured generation adjustments will be made. + + // Until we know better, desired promotion size uses the last calculation + size_t desired_promo_size = _promo_size; + + // Start eden at the current value. The desired value that is stored + // in _eden_size is not bounded by constraints of the heap and can + // run away. + // + // As expected setting desired_eden_size to the current + // value of desired_eden_size as a starting point + // caused desired_eden_size to grow way too large and caused + // an overflow down stream. It may have improved performance in + // some case but is dangerous. + size_t desired_eden_size = cur_eden; + + // Cache some values. There's a bit of work getting these, so + // we might save a little time. + const double major_cost = major_gc_cost(); + const double minor_cost = minor_gc_cost(); + + // Limits on our growth + size_t promo_limit = (size_t)(max_old_gen_size - avg_old_live()->average()); + + // But don't force a promo size below the current promo size. Otherwise, + // the promo size will shrink for no good reason. + promo_limit = MAX2(promo_limit, _promo_size); + + const double gc_cost_limit = GCTimeLimit/100.0; + + // Which way should we go? + // if pause requirement is not met + // adjust size of any generation with average paus exceeding + // the pause limit. Adjust one pause at a time (the larger) + // and only make adjustments for the major pause at full collections. + // else if throughput requirement not met + // adjust the size of the generation with larger gc time. Only + // adjust one generation at a time. + // else + // adjust down the total heap size. Adjust down the larger of the + // generations. + + // Add some checks for a threshhold for a change. For example, + // a change less than the necessary alignment is probably not worth + // attempting. + + if ((_avg_minor_pause->padded_average() > gc_pause_goal_sec()) || + (_avg_major_pause->padded_average() > gc_pause_goal_sec())) { + // + // Check pauses + // + // Make changes only to affect one of the pauses (the larger) + // at a time. + if (is_full_gc) { + set_decide_at_full_gc(decide_at_full_gc_true); + adjust_promo_for_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); + } + } else if (_avg_minor_pause->padded_average() > gc_minor_pause_goal_sec()) { + // Adjust only for the minor pause time goal + adjust_promo_for_minor_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); + } else if(adjusted_mutator_cost() < _throughput_goal) { + // This branch used to require that (mutator_cost() > 0.0 in 1.4.2. + // This sometimes resulted in skipping to the minimize footprint + // code. Change this to try and reduce GC time if mutator time is + // negative for whatever reason. Or for future consideration, + // bail out of the code if mutator time is negative. + // + // Throughput + // + assert(major_cost >= 0.0, "major cost is < 0.0"); + assert(minor_cost >= 0.0, "minor cost is < 0.0"); + // Try to reduce the GC times. + if (is_full_gc) { + set_decide_at_full_gc(decide_at_full_gc_true); + adjust_promo_for_throughput(is_full_gc, &desired_promo_size); + } + } else { + + // Be conservative about reducing the footprint. + // Do a minimum number of major collections first. + // Have reasonable averages for major and minor collections costs. + if (UseAdaptiveSizePolicyFootprintGoal && + young_gen_policy_is_ready() && + avg_major_gc_cost()->average() >= 0.0 && + avg_minor_gc_cost()->average() >= 0.0) { + if (is_full_gc) { + set_decide_at_full_gc(decide_at_full_gc_true); + size_t desired_sum = desired_eden_size + desired_promo_size; + desired_promo_size = adjust_promo_for_footprint(desired_promo_size, desired_sum); + } + } + } + + // Note we make the same tests as in the code block below; the code + // seems a little easier to read with the printing in another block. + if (PrintAdaptiveSizePolicy) { + if (desired_promo_size > promo_limit) { + // "free_in_old_gen" was the original value for used for promo_limit + size_t free_in_old_gen = (size_t)(max_old_gen_size - avg_old_live()->average()); + gclog_or_tty->print_cr( + "PSAdaptiveSizePolicy::compute_old_gen_free_space limits:" + " desired_promo_size: " SIZE_FORMAT + " promo_limit: " SIZE_FORMAT + " free_in_old_gen: " SIZE_FORMAT + " max_old_gen_size: " SIZE_FORMAT + " avg_old_live: " SIZE_FORMAT, + desired_promo_size, promo_limit, free_in_old_gen, + max_old_gen_size, (size_t) avg_old_live()->average()); + } + if (gc_cost() > gc_cost_limit) { + gclog_or_tty->print_cr( + "PSAdaptiveSizePolicy::compute_old_gen_free_space: gc time limit" + " gc_cost: %f " + " GCTimeLimit: %d", + gc_cost(), GCTimeLimit); + } + } + + // Align everything and make a final limit check + const size_t alignment = _intra_generation_alignment; + desired_promo_size = align_size_up(desired_promo_size, alignment); + desired_promo_size = MAX2(desired_promo_size, alignment); + + promo_limit = align_size_down(promo_limit, alignment); + + // And one last limit check, now that we've aligned things. + desired_promo_size = MIN2(desired_promo_size, promo_limit); + + if (PrintAdaptiveSizePolicy) { + // Timing stats + gclog_or_tty->print( + "PSAdaptiveSizePolicy::compute_old_gen_free_space: costs" + " minor_time: %f" + " major_cost: %f" + " mutator_cost: %f" + " throughput_goal: %f", + minor_gc_cost(), major_gc_cost(), mutator_cost(), + _throughput_goal); + + // We give more details if Verbose is set + if (Verbose) { + gclog_or_tty->print( " minor_pause: %f" + " major_pause: %f" + " minor_interval: %f" + " major_interval: %f" + " pause_goal: %f", + _avg_minor_pause->padded_average(), + _avg_major_pause->padded_average(), + _avg_minor_interval->average(), + _avg_major_interval->average(), + gc_pause_goal_sec()); + } + + // Footprint stats + gclog_or_tty->print( " live_space: " SIZE_FORMAT + " free_space: " SIZE_FORMAT, + live_space(), free_space()); + // More detail + if (Verbose) { + gclog_or_tty->print( " base_footprint: " SIZE_FORMAT + " avg_young_live: " SIZE_FORMAT + " avg_old_live: " SIZE_FORMAT, + (size_t)_avg_base_footprint->average(), + (size_t)avg_young_live()->average(), + (size_t)avg_old_live()->average()); + } + + // And finally, our old and new sizes. + gclog_or_tty->print(" old_promo_size: " SIZE_FORMAT + " desired_promo_size: " SIZE_FORMAT, + _promo_size, desired_promo_size); + gclog_or_tty->cr(); + } set_promo_size(desired_promo_size); - set_eden_size(desired_eden_size); -}; +} void PSAdaptiveSizePolicy::decay_supplemental_growth(bool is_full_gc) { // Decay the supplemental increment? Decay the supplement growth @@ -490,42 +642,24 @@ } } -void PSAdaptiveSizePolicy::adjust_for_minor_pause_time(bool is_full_gc, +void PSAdaptiveSizePolicy::adjust_promo_for_minor_pause_time(bool is_full_gc, size_t* desired_promo_size_ptr, size_t* desired_eden_size_ptr) { - // Adjust the young generation size to reduce pause time of - // of collections. - // - // The AdaptiveSizePolicyInitializingSteps test is not used - // here. It has not seemed to be needed but perhaps should - // be added for consistency. - if (minor_pause_young_estimator()->decrement_will_decrease()) { - // reduce eden size - set_change_young_gen_for_min_pauses( - decrease_young_gen_for_min_pauses_true); - *desired_eden_size_ptr = *desired_eden_size_ptr - - eden_decrement_aligned_down(*desired_eden_size_ptr); - } else { - // EXPERIMENTAL ADJUSTMENT - // Only record that the estimator indicated such an action. - // *desired_eden_size_ptr = *desired_eden_size_ptr + eden_heap_delta; - set_change_young_gen_for_min_pauses( - increase_young_gen_for_min_pauses_true); - } if (PSAdjustTenuredGenForMinorPause) { + if (is_full_gc) { + set_decide_at_full_gc(decide_at_full_gc_true); + } // If the desired eden size is as small as it will get, // try to adjust the old gen size. if (*desired_eden_size_ptr <= _intra_generation_alignment) { // Vary the old gen size to reduce the young gen pause. This // may not be a good idea. This is just a test. if (minor_pause_old_estimator()->decrement_will_decrease()) { - set_change_old_gen_for_min_pauses( - decrease_old_gen_for_min_pauses_true); + set_change_old_gen_for_min_pauses(decrease_old_gen_for_min_pauses_true); *desired_promo_size_ptr = _promo_size - promo_decrement_aligned_down(*desired_promo_size_ptr); } else { - set_change_old_gen_for_min_pauses( - increase_old_gen_for_min_pauses_true); + set_change_old_gen_for_min_pauses(increase_old_gen_for_min_pauses_true); size_t promo_heap_delta = promo_increment_with_supplement_aligned_up(*desired_promo_size_ptr); if ((*desired_promo_size_ptr + promo_heap_delta) > @@ -538,23 +672,41 @@ } } -void PSAdaptiveSizePolicy::adjust_for_pause_time(bool is_full_gc, +void PSAdaptiveSizePolicy::adjust_eden_for_minor_pause_time(bool is_full_gc, + size_t* desired_eden_size_ptr) { + + // Adjust the young generation size to reduce pause time of + // of collections. + // + // The AdaptiveSizePolicyInitializingSteps test is not used + // here. It has not seemed to be needed but perhaps should + // be added for consistency. + if (minor_pause_young_estimator()->decrement_will_decrease()) { + // reduce eden size + set_change_young_gen_for_min_pauses( + decrease_young_gen_for_min_pauses_true); + *desired_eden_size_ptr = *desired_eden_size_ptr - + eden_decrement_aligned_down(*desired_eden_size_ptr); + } else { + // EXPERIMENTAL ADJUSTMENT + // Only record that the estimator indicated such an action. + // *desired_eden_size_ptr = *desired_eden_size_ptr + eden_heap_delta; + set_change_young_gen_for_min_pauses( + increase_young_gen_for_min_pauses_true); + } +} + +void PSAdaptiveSizePolicy::adjust_promo_for_pause_time(bool is_full_gc, size_t* desired_promo_size_ptr, size_t* desired_eden_size_ptr) { size_t promo_heap_delta = 0; - size_t eden_heap_delta = 0; - // Add some checks for a threshhold for a change. For example, + // Add some checks for a threshold for a change. For example, // a change less than the required alignment is probably not worth // attempting. - if (is_full_gc) { - set_decide_at_full_gc(decide_at_full_gc_true); - } if (_avg_minor_pause->padded_average() > _avg_major_pause->padded_average()) { - adjust_for_minor_pause_time(is_full_gc, - desired_promo_size_ptr, - desired_eden_size_ptr); + adjust_promo_for_minor_pause_time(is_full_gc, desired_promo_size_ptr, desired_eden_size_ptr); // major pause adjustments } else if (is_full_gc) { // Adjust for the major pause time only at full gc's because the @@ -573,6 +725,33 @@ // promo_increment_aligned_up(*desired_promo_size_ptr); set_change_old_gen_for_maj_pauses(increase_old_gen_for_maj_pauses_true); } + } + + if (PrintAdaptiveSizePolicy && Verbose) { + gclog_or_tty->print_cr( + "PSAdaptiveSizePolicy::compute_old_gen_free_space " + "adjusting gen sizes for major pause (avg %f goal %f). " + "desired_promo_size " SIZE_FORMAT " promo delta " SIZE_FORMAT, + _avg_major_pause->average(), gc_pause_goal_sec(), + *desired_promo_size_ptr, promo_heap_delta); + } +} + +void PSAdaptiveSizePolicy::adjust_eden_for_pause_time(bool is_full_gc, + size_t* desired_promo_size_ptr, + size_t* desired_eden_size_ptr) { + + size_t eden_heap_delta = 0; + // Add some checks for a threshold for a change. For example, + // a change less than the required alignment is probably not worth + // attempting. + if (_avg_minor_pause->padded_average() > _avg_major_pause->padded_average()) { + adjust_eden_for_minor_pause_time(is_full_gc, + desired_eden_size_ptr); + // major pause adjustments + } else if (is_full_gc) { + // Adjust for the major pause time only at full gc's because the + // affects of a change can only be seen at full gc's. if (PSAdjustYoungGenForMajorPause) { // If the promo size is at the minimum (i.e., the old gen // size will not actually decrease), consider changing the @@ -607,43 +786,35 @@ if (PrintAdaptiveSizePolicy && Verbose) { gclog_or_tty->print_cr( - "AdaptiveSizePolicy::compute_generation_free_space " + "PSAdaptiveSizePolicy::compute_eden_space_size " "adjusting gen sizes for major pause (avg %f goal %f). " - "desired_promo_size " SIZE_FORMAT "desired_eden_size " - SIZE_FORMAT - " promo delta " SIZE_FORMAT " eden delta " SIZE_FORMAT, + "desired_eden_size " SIZE_FORMAT " eden delta " SIZE_FORMAT, _avg_major_pause->average(), gc_pause_goal_sec(), - *desired_promo_size_ptr, *desired_eden_size_ptr, - promo_heap_delta, eden_heap_delta); + *desired_eden_size_ptr, eden_heap_delta); } } -void PSAdaptiveSizePolicy::adjust_for_throughput(bool is_full_gc, - size_t* desired_promo_size_ptr, - size_t* desired_eden_size_ptr) { +void PSAdaptiveSizePolicy::adjust_promo_for_throughput(bool is_full_gc, + size_t* desired_promo_size_ptr) { - // Add some checks for a threshhold for a change. For example, + // Add some checks for a threshold for a change. For example, // a change less than the required alignment is probably not worth // attempting. - if (is_full_gc) { - set_decide_at_full_gc(decide_at_full_gc_true); - } if ((gc_cost() + mutator_cost()) == 0.0) { return; } if (PrintAdaptiveSizePolicy && Verbose) { - gclog_or_tty->print("\nPSAdaptiveSizePolicy::adjust_for_throughput(" - "is_full: %d, promo: " SIZE_FORMAT ", cur_eden: " SIZE_FORMAT "): ", - is_full_gc, *desired_promo_size_ptr, *desired_eden_size_ptr); + gclog_or_tty->print("\nPSAdaptiveSizePolicy::adjust_promo_for_throughput(" + "is_full: %d, promo: " SIZE_FORMAT "): ", + is_full_gc, *desired_promo_size_ptr); gclog_or_tty->print_cr("mutator_cost %f major_gc_cost %f " "minor_gc_cost %f", mutator_cost(), major_gc_cost(), minor_gc_cost()); } // Tenured generation if (is_full_gc) { - // Calculate the change to use for the tenured gen. size_t scaled_promo_heap_delta = 0; // Can the increment to the generation be scaled? @@ -720,6 +891,26 @@ *desired_promo_size_ptr, scaled_promo_heap_delta); } } +} + +void PSAdaptiveSizePolicy::adjust_eden_for_throughput(bool is_full_gc, + size_t* desired_eden_size_ptr) { + + // Add some checks for a threshold for a change. For example, + // a change less than the required alignment is probably not worth + // attempting. + + if ((gc_cost() + mutator_cost()) == 0.0) { + return; + } + + if (PrintAdaptiveSizePolicy && Verbose) { + gclog_or_tty->print("\nPSAdaptiveSizePolicy::adjust_eden_for_throughput(" + "is_full: %d, cur_eden: " SIZE_FORMAT "): ", + is_full_gc, *desired_eden_size_ptr); + gclog_or_tty->print_cr("mutator_cost %f major_gc_cost %f " + "minor_gc_cost %f", mutator_cost(), major_gc_cost(), minor_gc_cost()); + } // Young generation size_t scaled_eden_heap_delta = 0;