1 /*

     2  * Copyright (c) 2018, 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/parallel/heterogeneousGenerationSizer.hpp"

    27 #include "gc/shared/collectorPolicy.hpp"

    28 #include "logging/log.hpp"

    29 #include "runtime/globals_extension.hpp"

    30 #include "runtime/os.hpp"

    31 #include "utilities/align.hpp"

    32 #include "utilities/formatBuffer.hpp"

    33 #include "utilities/globalDefinitions.hpp"

    34 

    35 const double HeterogeneousGenerationSizer::MaxRamFractionForYoung = 0.8;

    36 

    37 // Check the available dram memory to limit NewSize and MaxNewSize before

    38 // calling base class initialize_flags().

    39 void HeterogeneousGenerationSizer::initialize_flags() {

    40   FormatBuffer<100> calc_str("");

    41 

    42   julong phys_mem;

    43   // If MaxRam is specified, we use that as maximum physical memory available.

    44   if (FLAG_IS_DEFAULT(MaxRAM)) {

    45     phys_mem = os::physical_memory();

    46     calc_str.append("Physical_Memory");

    47   } else {

    48     phys_mem = (julong)MaxRAM;

    49     calc_str.append("MaxRAM");

    50   }

    51 

    52   julong reasonable_max = phys_mem;

    53 

    54   // If either MaxRAMFraction or MaxRAMPercentage is specified, we use them to calculate

    55   // reasonable max size of young generation.

    56   if (!FLAG_IS_DEFAULT(MaxRAMFraction)) {

    57     reasonable_max = (julong)(phys_mem / MaxRAMFraction);

    58     calc_str.append(" / MaxRAMFraction");

    59   } else if (!FLAG_IS_DEFAULT(MaxRAMPercentage)) {

    60     reasonable_max = (julong)((phys_mem * MaxRAMPercentage) / 100);

    61     calc_str.append(" * MaxRAMPercentage / 100");

    62   } else {

    63     // We use our own fraction to calculate max size of young generation.

    64     reasonable_max = phys_mem * MaxRamFractionForYoung;

    65     calc_str.append(" * %0.2f", MaxRamFractionForYoung);

    66   }

    67   reasonable_max = align_up(reasonable_max, _gen_alignment);

    68 

    69   if (MaxNewSize > reasonable_max) {

    70     if (FLAG_IS_CMDLINE(MaxNewSize)) {

    71       log_warning(gc, ergo)("Setting MaxNewSize to " SIZE_FORMAT " based on dram available (calculation = align(%s))",

    72                             (size_t)reasonable_max, calc_str.buffer());

    73     } else {

    74       log_info(gc, ergo)("Setting MaxNewSize to " SIZE_FORMAT " based on dram available (calculation = align(%s)). "

    75                          "Dram usage can be lowered by setting MaxNewSize to a lower value", (size_t)reasonable_max, calc_str.buffer());

    76     }

    77     MaxNewSize = reasonable_max;

    78   }

    79   if (NewSize > reasonable_max) {

    80     if (FLAG_IS_CMDLINE(NewSize)) {

    81       log_warning(gc, ergo)("Setting NewSize to " SIZE_FORMAT " based on dram available (calculation = align(%s))",

    82                             (size_t)reasonable_max, calc_str.buffer());

    83     }

    84     NewSize = reasonable_max;

    85   }

    86 

    87   // After setting new size flags, call base class initialize_flags()

    88   GenerationSizer::initialize_flags();

    89 }

    90 

    91 bool HeterogeneousGenerationSizer::is_hetero_heap() const {

    92   return true;

    93 }

    94 

    95 size_t HeterogeneousGenerationSizer::heap_reserved_size_bytes() const {

    96   if (UseAdaptiveGCBoundary) {

    97     // This is the size that young gen can grow to, when UseAdaptiveGCBoundary is true.

    98     size_t max_yg_size = _max_heap_byte_size - _min_old_size;

    99     // This is the size that old gen can grow to, when UseAdaptiveGCBoundary is true.

   100     size_t max_old_size = _max_heap_byte_size - _min_young_size;

   101 

   102     return max_yg_size + max_old_size;

   103   } else {

   104     return _max_heap_byte_size;

   105   }

   106 }