--- a/src/hotspot/share/gc/cms/allocationStats.hpp Fri Nov 08 14:54:17 2019 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,154 +0,0 @@
-/*
- * Copyright (c) 2001, 2019, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * 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 www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-#ifndef SHARE_GC_CMS_ALLOCATIONSTATS_HPP
-#define SHARE_GC_CMS_ALLOCATIONSTATS_HPP
-
-#include "gc/shared/gcUtil.hpp"
-#include "logging/log.hpp"
-#include "runtime/globals.hpp"
-#include "utilities/globalDefinitions.hpp"
-#include "utilities/macros.hpp"
-
-class AllocationStats {
- // A duration threshold (in ms) used to filter
- // possibly unreliable samples.
- static float _threshold;
-
- // We measure the demand between the end of the previous sweep and
- // beginning of this sweep:
- // Count(end_last_sweep) - Count(start_this_sweep)
- // + split_births(between) - split_deaths(between)
- // The above number divided by the time since the end of the
- // previous sweep gives us a time rate of demand for blocks
- // of this size. We compute a padded average of this rate as
- // our current estimate for the time rate of demand for blocks
- // of this size. Similarly, we keep a padded average for the time
- // between sweeps. Our current estimate for demand for blocks of
- // this size is then simply computed as the product of these two
- // estimates.
- AdaptivePaddedAverage _demand_rate_estimate;
-
- ssize_t _desired; // Demand estimate computed as described above
- ssize_t _coal_desired; // desired +/- small-percent for tuning coalescing
-
- ssize_t _surplus; // count - (desired +/- small-percent),
- // used to tune splitting in best fit
- ssize_t _bfr_surp; // surplus at start of current sweep
- ssize_t _prev_sweep; // count from end of previous sweep
- ssize_t _before_sweep; // count from before current sweep
- ssize_t _coal_births; // additional chunks from coalescing
- ssize_t _coal_deaths; // loss from coalescing
- ssize_t _split_births; // additional chunks from splitting
- ssize_t _split_deaths; // loss from splitting
- size_t _returned_bytes; // number of bytes returned to list.
- public:
- void initialize(bool split_birth = false);
-
- AllocationStats() {
- initialize();
- }
-
- // The rate estimate is in blocks per second.
- void compute_desired(size_t count,
- float inter_sweep_current,
- float inter_sweep_estimate,
- float intra_sweep_estimate) {
- // If the latest inter-sweep time is below our granularity
- // of measurement, we may call in here with
- // inter_sweep_current == 0. However, even for suitably small
- // but non-zero inter-sweep durations, we may not trust the accuracy
- // of accumulated data, since it has not been "integrated"
- // (read "low-pass-filtered") long enough, and would be
- // vulnerable to noisy glitches. In such cases, we
- // ignore the current sample and use currently available
- // historical estimates.
- assert(prev_sweep() + split_births() + coal_births() // "Total Production Stock"
- >= split_deaths() + coal_deaths() + (ssize_t)count, // "Current stock + depletion"
- "Conservation Principle");
- if (inter_sweep_current > _threshold) {
- ssize_t demand = prev_sweep() - (ssize_t)count + split_births() + coal_births()
- - split_deaths() - coal_deaths();
- assert(demand >= 0,
- "Demand (" SSIZE_FORMAT ") should be non-negative for "
- PTR_FORMAT " (size=" SIZE_FORMAT ")",
- demand, p2i(this), count);
- // Defensive: adjust for imprecision in event counting
- if (demand < 0) {
- demand = 0;
- }
- float old_rate = _demand_rate_estimate.padded_average();
- float rate = ((float)demand)/inter_sweep_current;
- _demand_rate_estimate.sample(rate);
- float new_rate = _demand_rate_estimate.padded_average();
- ssize_t old_desired = _desired;
- float delta_ise = (CMSExtrapolateSweep ? intra_sweep_estimate : 0.0);
- _desired = (ssize_t)(new_rate * (inter_sweep_estimate + delta_ise));
- log_trace(gc, freelist)("demand: " SSIZE_FORMAT ", old_rate: %f, current_rate: %f, "
- "new_rate: %f, old_desired: " SSIZE_FORMAT ", new_desired: " SSIZE_FORMAT,
- demand, old_rate, rate, new_rate, old_desired, _desired);
- }
- }
-
- ssize_t desired() const { return _desired; }
- void set_desired(ssize_t v) { _desired = v; }
-
- ssize_t coal_desired() const { return _coal_desired; }
- void set_coal_desired(ssize_t v) { _coal_desired = v; }
-
- ssize_t surplus() const { return _surplus; }
- void set_surplus(ssize_t v) { _surplus = v; }
- void increment_surplus() { _surplus++; }
- void decrement_surplus() { _surplus--; }
-
- ssize_t bfr_surp() const { return _bfr_surp; }
- void set_bfr_surp(ssize_t v) { _bfr_surp = v; }
- ssize_t prev_sweep() const { return _prev_sweep; }
- void set_prev_sweep(ssize_t v) { _prev_sweep = v; }
- ssize_t before_sweep() const { return _before_sweep; }
- void set_before_sweep(ssize_t v) { _before_sweep = v; }
-
- ssize_t coal_births() const { return _coal_births; }
- void set_coal_births(ssize_t v) { _coal_births = v; }
- void increment_coal_births() { _coal_births++; }
-
- ssize_t coal_deaths() const { return _coal_deaths; }
- void set_coal_deaths(ssize_t v) { _coal_deaths = v; }
- void increment_coal_deaths() { _coal_deaths++; }
-
- ssize_t split_births() const { return _split_births; }
- void set_split_births(ssize_t v) { _split_births = v; }
- void increment_split_births() { _split_births++; }
-
- ssize_t split_deaths() const { return _split_deaths; }
- void set_split_deaths(ssize_t v) { _split_deaths = v; }
- void increment_split_deaths() { _split_deaths++; }
-
- NOT_PRODUCT(
- size_t returned_bytes() const { return _returned_bytes; }
- void set_returned_bytes(size_t v) { _returned_bytes = v; }
- )
-};
-
-#endif // SHARE_GC_CMS_ALLOCATIONSTATS_HPP