1.1 --- a/src/share/vm/memory/allocationStats.hpp Tue Feb 26 15:57:49 2008 -0800
1.2 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000
1.3 @@ -1,136 +0,0 @@
1.4 -/*
1.5 - * Copyright 2001-2005 Sun Microsystems, Inc. All Rights Reserved.
1.6 - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 - *
1.8 - * This code is free software; you can redistribute it and/or modify it
1.9 - * under the terms of the GNU General Public License version 2 only, as
1.10 - * published by the Free Software Foundation.
1.11 - *
1.12 - * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 - * version 2 for more details (a copy is included in the LICENSE file that
1.16 - * accompanied this code).
1.17 - *
1.18 - * You should have received a copy of the GNU General Public License version
1.19 - * 2 along with this work; if not, write to the Free Software Foundation,
1.20 - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 - *
1.22 - * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
1.23 - * CA 95054 USA or visit www.sun.com if you need additional information or
1.24 - * have any questions.
1.25 - *
1.26 - */
1.27 -
1.28 -class AllocationStats VALUE_OBJ_CLASS_SPEC {
1.29 - // A duration threshold (in ms) used to filter
1.30 - // possibly unreliable samples.
1.31 - static float _threshold;
1.32 -
1.33 - // We measure the demand between the end of the previous sweep and
1.34 - // beginning of this sweep:
1.35 - // Count(end_last_sweep) - Count(start_this_sweep)
1.36 - // + splitBirths(between) - splitDeaths(between)
1.37 - // The above number divided by the time since the start [END???] of the
1.38 - // previous sweep gives us a time rate of demand for blocks
1.39 - // of this size. We compute a padded average of this rate as
1.40 - // our current estimate for the time rate of demand for blocks
1.41 - // of this size. Similarly, we keep a padded average for the time
1.42 - // between sweeps. Our current estimate for demand for blocks of
1.43 - // this size is then simply computed as the product of these two
1.44 - // estimates.
1.45 - AdaptivePaddedAverage _demand_rate_estimate;
1.46 -
1.47 - ssize_t _desired; // Estimate computed as described above
1.48 - ssize_t _coalDesired; // desired +/- small-percent for tuning coalescing
1.49 -
1.50 - ssize_t _surplus; // count - (desired +/- small-percent),
1.51 - // used to tune splitting in best fit
1.52 - ssize_t _bfrSurp; // surplus at start of current sweep
1.53 - ssize_t _prevSweep; // count from end of previous sweep
1.54 - ssize_t _beforeSweep; // count from before current sweep
1.55 - ssize_t _coalBirths; // additional chunks from coalescing
1.56 - ssize_t _coalDeaths; // loss from coalescing
1.57 - ssize_t _splitBirths; // additional chunks from splitting
1.58 - ssize_t _splitDeaths; // loss from splitting
1.59 - size_t _returnedBytes; // number of bytes returned to list.
1.60 - public:
1.61 - void initialize() {
1.62 - AdaptivePaddedAverage* dummy =
1.63 - new (&_demand_rate_estimate) AdaptivePaddedAverage(CMS_FLSWeight,
1.64 - CMS_FLSPadding);
1.65 - _desired = 0;
1.66 - _coalDesired = 0;
1.67 - _surplus = 0;
1.68 - _bfrSurp = 0;
1.69 - _prevSweep = 0;
1.70 - _beforeSweep = 0;
1.71 - _coalBirths = 0;
1.72 - _coalDeaths = 0;
1.73 - _splitBirths = 0;
1.74 - _splitDeaths = 0;
1.75 - _returnedBytes = 0;
1.76 - }
1.77 -
1.78 - AllocationStats() {
1.79 - initialize();
1.80 - }
1.81 - // The rate estimate is in blocks per second.
1.82 - void compute_desired(size_t count,
1.83 - float inter_sweep_current,
1.84 - float inter_sweep_estimate) {
1.85 - // If the latest inter-sweep time is below our granularity
1.86 - // of measurement, we may call in here with
1.87 - // inter_sweep_current == 0. However, even for suitably small
1.88 - // but non-zero inter-sweep durations, we may not trust the accuracy
1.89 - // of accumulated data, since it has not been "integrated"
1.90 - // (read "low-pass-filtered") long enough, and would be
1.91 - // vulnerable to noisy glitches. In such cases, we
1.92 - // ignore the current sample and use currently available
1.93 - // historical estimates.
1.94 - if (inter_sweep_current > _threshold) {
1.95 - ssize_t demand = prevSweep() - count + splitBirths() - splitDeaths();
1.96 - float rate = ((float)demand)/inter_sweep_current;
1.97 - _demand_rate_estimate.sample(rate);
1.98 - _desired = (ssize_t)(_demand_rate_estimate.padded_average()
1.99 - *inter_sweep_estimate);
1.100 - }
1.101 - }
1.102 -
1.103 - ssize_t desired() const { return _desired; }
1.104 - ssize_t coalDesired() const { return _coalDesired; }
1.105 - void set_coalDesired(ssize_t v) { _coalDesired = v; }
1.106 -
1.107 - ssize_t surplus() const { return _surplus; }
1.108 - void set_surplus(ssize_t v) { _surplus = v; }
1.109 - void increment_surplus() { _surplus++; }
1.110 - void decrement_surplus() { _surplus--; }
1.111 -
1.112 - ssize_t bfrSurp() const { return _bfrSurp; }
1.113 - void set_bfrSurp(ssize_t v) { _bfrSurp = v; }
1.114 - ssize_t prevSweep() const { return _prevSweep; }
1.115 - void set_prevSweep(ssize_t v) { _prevSweep = v; }
1.116 - ssize_t beforeSweep() const { return _beforeSweep; }
1.117 - void set_beforeSweep(ssize_t v) { _beforeSweep = v; }
1.118 -
1.119 - ssize_t coalBirths() const { return _coalBirths; }
1.120 - void set_coalBirths(ssize_t v) { _coalBirths = v; }
1.121 - void increment_coalBirths() { _coalBirths++; }
1.122 -
1.123 - ssize_t coalDeaths() const { return _coalDeaths; }
1.124 - void set_coalDeaths(ssize_t v) { _coalDeaths = v; }
1.125 - void increment_coalDeaths() { _coalDeaths++; }
1.126 -
1.127 - ssize_t splitBirths() const { return _splitBirths; }
1.128 - void set_splitBirths(ssize_t v) { _splitBirths = v; }
1.129 - void increment_splitBirths() { _splitBirths++; }
1.130 -
1.131 - ssize_t splitDeaths() const { return _splitDeaths; }
1.132 - void set_splitDeaths(ssize_t v) { _splitDeaths = v; }
1.133 - void increment_splitDeaths() { _splitDeaths++; }
1.134 -
1.135 - NOT_PRODUCT(
1.136 - size_t returnedBytes() const { return _returnedBytes; }
1.137 - void set_returnedBytes(size_t v) { _returnedBytes = v; }
1.138 - )
1.139 -};
