1 /* 2 * Copyright (c) 2015, 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/g1/g1Predictions.hpp" 27 28 #ifndef PRODUCT 29 30 void G1Predictions::test() { 31 double const epsilon = 1e-6; 32 { 33 // Some basic formula tests with confidence = 0.0 34 G1Predictions predictor(0.0); 35 TruncatedSeq s; 36 37 double p0 = predictor.get_new_prediction(&s); 38 assert(p0 < epsilon, "Initial prediction of empty sequence must be 0.0 but is %f", p0); 39 40 s.add(5.0); 41 double p1 = predictor.get_new_prediction(&s); 42 assert(fabs(p1 - 5.0) < epsilon, "Prediction should be 5.0 but is %f", p1); 43 for (int i = 0; i < 40; i++) { 44 s.add(5.0); 45 } 46 double p2 = predictor.get_new_prediction(&s); 47 assert(fabs(p2 - 5.0) < epsilon, "Prediction should be 5.0 but is %f", p1); 48 } 49 50 { 51 // The following tests checks that the initial predictions are based on the 52 // average of the sequence and not on the stddev (which is 0). 53 G1Predictions predictor(0.5); 54 TruncatedSeq s; 55 56 s.add(1.0); 57 double p1 = predictor.get_new_prediction(&s); 58 assert(p1 > 1.0, "First prediction must be larger than average, but avg is %f and prediction %f", s.davg(), p1); 59 s.add(1.0); 60 double p2 = predictor.get_new_prediction(&s); 61 assert(p2 < p1, "First prediction must be larger than second, but they are %f %f", p1, p2); 62 s.add(1.0); 63 double p3 = predictor.get_new_prediction(&s); 64 assert(p3 < p2, "Second prediction must be larger than third, but they are %f %f", p2, p3); 65 s.add(1.0); 66 s.add(1.0); // Five elements are now in the sequence. 67 double p5 = predictor.get_new_prediction(&s); 68 assert(p5 < p3, "Fifth prediction must be smaller than third, but they are %f %f", p3, p5); 69 assert(fabs(p5 - 1.0) < epsilon, "Prediction must be 1.0+epsilon, but is %f", p5); 70 } 71 72 { 73 // The following tests checks that initially prediction based on the average is 74 // used, that gets overridden by the stddev prediction at the end. 75 G1Predictions predictor(0.5); 76 TruncatedSeq s; 77 78 s.add(0.5); 79 double p1 = predictor.get_new_prediction(&s); 80 assert(p1 > 0.5, "First prediction must be larger than average, but avg is %f and prediction %f", s.davg(), p1); 81 s.add(0.2); 82 double p2 = predictor.get_new_prediction(&s); 83 assert(p2 < p1, "First prediction must be larger than second, but they are %f %f", p1, p2); 84 s.add(0.5); 85 double p3 = predictor.get_new_prediction(&s); 86 assert(p3 < p2, "Second prediction must be larger than third, but they are %f %f", p2, p3); 87 s.add(0.2); 88 s.add(2.0); 89 double p5 = predictor.get_new_prediction(&s); 90 assert(p5 > p3, "Fifth prediction must be bigger than third, but they are %f %f", p3, p5); 91 } 92 } 93 94 void TestPredictions_test() { 95 G1Predictions::test(); 96 } 97 98 #endif