view src/share/vm/gc_implementation/g1/g1ErgoVerbose.hpp @ 3414:a9647476d1a4

7132029: G1: mixed GC phase lasts for longer than it should Summary: Revamp of the mechanism that chooses old regions for inclusion in the CSet. It simplifies the code and introduces min and max bounds on the number of old regions added to the CSet at each mixed GC to avoid pathological cases. It also ensures that when we do a mixed GC we'll always find old regions to add to the CSet (i.e., it eliminates the case where a mixed GC will collect no old regions which can happen today). Reviewed-by: johnc, brutisso
author tonyp
date Wed, 15 Feb 2012 13:06:53 -0500
parents 41406797186b
children 720b6a76dd9d
line wrap: on
line source
 * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit if you need additional information or have any
 * questions.


#include "memory/allocation.hpp"
#include "utilities/debug.hpp"

// The log of G1's heuristic decisions comprises of a series of
// records which have a similar format in order to maintain
// consistency across records and ultimately easier parsing of the
// output, if we ever choose to do that. Each record consists of:
// * A time stamp to be able to easily correlate each record with
// other events.
// * A unique string to allow us to easily identify such records.
// * The name of the heuristic the record corresponds to.
// * An action string which describes the action that G1 did or is
// about to do.
// * An optional reason string which describes the reason for the
// action.
// * An optional number of name/value pairs which contributed to the
// decision to take the action described in the record.
// Each record is associated with a "tag" which is the combination of
// the heuristic the record corresponds to, as well as the min level
// of verboseness at which the record should be printed. The tag is
// checked against the current settings to determine whether the record
// should be printed or not.

// The available verboseness levels.
typedef enum {
  // Determine which part of the tag is occupied by the level.
  ErgoLevelShift = 8,
  ErgoLevelMask = ~((1 << ErgoLevelShift) - 1),

  // ErgoLow is 0 so that we don't have to explicitly or a heuristic
  // id with ErgoLow to keep its use simpler.
  ErgoLow = 0,
  ErgoHigh = 1 << ErgoLevelShift
} ErgoLevel;

// The available heuristics.
typedef enum {
  // Determines which part of the tag is occupied by the heuristic id.
  ErgoHeuristicMask = ~ErgoLevelMask,

  ErgoHeapSizing = 0,

} ErgoHeuristic;

class G1ErgoVerbose : AllStatic {
  // Determines the minimum verboseness level at which records will be
  // printed.
  static ErgoLevel _level;
  // Determines which heuristics are currently enabled.
  static bool _enabled[ErgoHeuristicNum];

  static ErgoLevel extract_level(int tag) {
    return (ErgoLevel) (tag & ErgoLevelMask);

  static ErgoHeuristic extract_heuristic(int tag) {
    return (ErgoHeuristic) (tag & ErgoHeuristicMask);

  // Needs to be explicitly called at GC initialization.
  static void initialize();

  static void set_level(ErgoLevel level);
  static void set_enabled(ErgoHeuristic h, bool enabled);
  // It is applied to all heuristics.
  static void set_enabled(bool enabled);

  static bool enabled(int tag) {
    ErgoLevel level = extract_level(tag);
    ErgoHeuristic n = extract_heuristic(tag);
    return level <= _level && _enabled[n];

  // Extract the heuristic id from the tag and return a string with
  // its name.
  static const char* to_string(int tag);

// The macros below generate the format string for values of different
// types and/or metrics.

// The reason for the action is optional and is handled specially: the
// reason string is concatenated here so it's not necessary to pass it
// as a parameter.
#define ergo_format_reason(_reason_) ", reason: " _reason_

// Single parameter format strings
#define ergo_format_str(_name_)      ", " _name_ ": %s"
#define ergo_format_region(_name_)   ", " _name_ ": "SIZE_FORMAT" regions"
#define ergo_format_byte(_name_)     ", " _name_ ": "SIZE_FORMAT" bytes"
#define ergo_format_double(_name_)   ", " _name_ ": %1.2f"
#define ergo_format_perc(_name_)     ", " _name_ ": %1.2f %%"
#define ergo_format_ms(_name_)       ", " _name_ ": %1.2f ms"

// Double parameter format strings
#define ergo_format_byte_perc(_name_)                                   \
                             ", " _name_ ": "SIZE_FORMAT" bytes (%1.2f %%)"

// Generates the format string
#define ergo_format(_extra_format_)                           \
  " %1.3f: [G1Ergonomics (%s) %s" _extra_format_ "]"

// Conditionally, prints an ergonomic decision record. _extra_format_
// is the format string for the optional items we'd like to print
// (i.e., the decision's reason and any associated values). This
// string should be built up using the ergo_*_format macros (see
// above) to ensure consistency.
// Since we cannot rely on the compiler supporting variable argument
// macros, this macro accepts a fixed number of arguments and passes
// them to the print method. For convenience, we have wrapper macros
// below which take a specific number of arguments and set the rest to
// a default value.
#define ergo_verbose_common(_tag_, _action_, _extra_format_,                \
                            _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, _arg5_) \
  do {                                                                      \
    if (G1ErgoVerbose::enabled((_tag_))) {                                  \
      gclog_or_tty->print_cr(ergo_format(_extra_format_),                   \
                             os::elapsedTime(),                             \
                             G1ErgoVerbose::to_string((_tag_)),             \
                             (_action_),                                    \
                             (_arg0_), (_arg1_), (_arg2_),                  \
                             (_arg3_), (_arg4_), (_arg5_));                 \
    }                                                                       \
  } while (0)

#define ergo_verbose(_tag_, _action_)                                   \
  ergo_verbose_common(_tag_, _action_, "", 0, 0, 0, 0, 0, 0)

#define ergo_verbose0(_tag_, _action_, _extra_format_)                  \
  ergo_verbose_common(_tag_, _action_, _extra_format_, 0, 0, 0, 0, 0, 0)

#define ergo_verbose1(_tag_, _action_, _extra_format_,                  \
                      _arg0_)                                           \
  ergo_verbose_common(_tag_, _action_, _extra_format_,                  \
                      _arg0_, 0, 0, 0, 0, 0)

#define ergo_verbose2(_tag_, _action_, _extra_format_,                  \
                      _arg0_, _arg1_)                                   \
  ergo_verbose_common(_tag_, _action_, _extra_format_,                  \
                      _arg0_, _arg1_, 0, 0, 0, 0)

#define ergo_verbose3(_tag_, _action_, _extra_format_,                  \
                      _arg0_, _arg1_, _arg2_)                           \
  ergo_verbose_common(_tag_, _action_, _extra_format_,                  \
                      _arg0_, _arg1_, _arg2_, 0, 0, 0)

#define ergo_verbose4(_tag_, _action_, _extra_format_,                  \
                      _arg0_, _arg1_, _arg2_, _arg3_)                   \
  ergo_verbose_common(_tag_, _action_, _extra_format_,                  \
                      _arg0_, _arg1_, _arg2_, _arg3_, 0, 0)

#define ergo_verbose5(_tag_, _action_, _extra_format_,                  \
                      _arg0_, _arg1_, _arg2_, _arg3_, _arg4_)           \
  ergo_verbose_common(_tag_, _action_, _extra_format_,                  \
                      _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, 0)

#define ergo_verbose6(_tag_, _action_, _extra_format_,                  \
                      _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, _arg5_)   \
  ergo_verbose_common(_tag_, _action_, _extra_format_,                  \
                      _arg0_, _arg1_, _arg2_, _arg3_, _arg4_, _arg5_)