1 /* 2 * Copyright (c) 2018, 2019, Red Hat, Inc. 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 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHNUMBERSEQ_HPP 26 #define SHARE_GC_SHENANDOAH_SHENANDOAHNUMBERSEQ_HPP 27 28 #include "utilities/numberSeq.hpp" 29 30 // HDR sequence stores the low-resolution high-dynamic-range values. 31 // It does so by maintaining the double array, where first array defines 32 // the magnitude of the value being stored, and the second array maintains 33 // the low resolution histogram within that magnitude. For example, storing 34 // 4.352819 * 10^3 increments the bucket _hdr[3][435]. This allows for 35 // memory efficient storage of huge amount of samples. 36 // 37 // Accepts positive numbers only. 38 class HdrSeq: public NumberSeq { 39 private: 40 enum PrivateConstants { 41 ValBuckets = 512, 42 MagBuckets = 24, 43 MagMinimum = -12 44 }; 45 int** _hdr; 46 47 public: 48 HdrSeq(); 49 ~HdrSeq(); 50 51 virtual void add(double val); 52 void add(const HdrSeq& other); 53 double percentile(double level) const; 54 void clear(); 55 }; 56 57 // Binary magnitude sequence stores the power-of-two histogram. 58 // It has very low memory requirements, and is thread-safe. When accuracy 59 // is not needed, it is preferred over HdrSeq. 60 class BinaryMagnitudeSeq : public CHeapObj<mtGC> { 61 private: 62 size_t _sum; 63 size_t* _mags; 64 65 public: 66 BinaryMagnitudeSeq(); 67 ~BinaryMagnitudeSeq(); 68 69 void add(size_t val); 70 size_t num() const; 71 size_t level(int level) const; 72 size_t sum() const; 73 int min_level() const; 74 int max_level() const; 75 void clear(); 76 }; 77 78 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHNUMBERSEQ_HPP --- EOF ---