| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "core/conf.h" |
| #include "core/htrace.h" |
| #include "sampler/sampler.h" |
| #include "test/test.h" |
| #include "util/log.h" |
| |
| #include <math.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| static struct htrace_conf *g_test_conf; |
| |
| static struct htrace_log *g_test_lg; |
| |
| static struct htracer *g_test_tracer; |
| |
| #define NUM_TEST_SAMPLES 1000 |
| |
| static int test_simple_sampler(const char *name, int expected) |
| { |
| struct htrace_conf *conf; |
| struct htrace_sampler *smp; |
| char confstr[256] = { 0 }; |
| int i; |
| |
| if (name) { |
| snprintf(confstr, sizeof(confstr), "%s=%s", |
| HTRACE_SAMPLER_KEY, name); |
| } |
| conf = htrace_conf_from_strs(confstr, ""); |
| EXPECT_NONNULL(conf); |
| smp = htrace_sampler_create(g_test_tracer, conf); |
| EXPECT_NONNULL(smp); |
| for (i = 0; i < NUM_TEST_SAMPLES; i++) { |
| int s = smp->ty->next(smp); |
| EXPECT_INT_EQ(expected, s); |
| } |
| htrace_conf_free(conf); |
| htrace_sampler_free(smp); |
| return EXIT_SUCCESS; |
| } |
| |
| static int test_unconfigured_sampler() |
| { |
| return test_simple_sampler(NULL, 0); |
| } |
| |
| static int test_never_sampler() |
| { |
| return test_simple_sampler("never", 0); |
| } |
| |
| static int test_always_sampler() |
| { |
| return test_simple_sampler("always", 1); |
| } |
| |
| #define NUM_PROB_TEST_SAMPLES 500000 |
| |
| static int test_prob_sampler(double target, double slop) |
| { |
| struct htrace_conf *conf; |
| struct htrace_sampler *smp; |
| char confstr[256] = { 0 }; |
| double actual, diff; |
| |
| snprintf(confstr, sizeof(confstr), |
| "sampler=prob;prob.sampler.fraction=%g", target); |
| conf = htrace_conf_from_strs(confstr, ""); |
| EXPECT_NONNULL(conf); |
| smp = htrace_sampler_create(g_test_tracer, conf); |
| EXPECT_NONNULL(smp); |
| do { |
| int i; |
| uint64_t total = 0; |
| |
| for (i = 0; i < NUM_PROB_TEST_SAMPLES; i++) { |
| int val = smp->ty->next(smp); |
| if ((val != 0) && (val != 1)) { |
| htrace_log(g_test_lg, "Invalid return from sampler: " |
| "expected 0 or 1, but got %d\n", val); |
| abort(); |
| } |
| total += val; |
| } |
| actual = ((double)total) / (double)NUM_PROB_TEST_SAMPLES; |
| diff = fabs(target - actual); |
| htrace_log(g_test_lg, "After %d samples, fraction is %g. Target " |
| "was %g. %s\n", NUM_PROB_TEST_SAMPLES, actual, target, |
| (diff < slop) ? "Done. " : "Retrying."); |
| } while (diff >= slop); |
| htrace_conf_free(conf); |
| htrace_sampler_free(smp); |
| return EXIT_SUCCESS; |
| } |
| |
| int main(void) |
| { |
| g_test_conf = htrace_conf_from_strs("", HTRACE_TRACER_ID"=sampler-unit"); |
| EXPECT_NONNULL(g_test_conf); |
| g_test_lg = htrace_log_alloc(g_test_conf); |
| EXPECT_NONNULL(g_test_lg); |
| g_test_tracer = htracer_create("sampler-unit", g_test_conf); |
| EXPECT_NONNULL(g_test_tracer); |
| |
| EXPECT_INT_ZERO(test_unconfigured_sampler()); |
| EXPECT_INT_ZERO(test_never_sampler()); |
| EXPECT_INT_ZERO(test_always_sampler()); |
| EXPECT_INT_ZERO(test_prob_sampler(0.5, 0.001)); |
| EXPECT_INT_ZERO(test_prob_sampler(0.01, 0.001)); |
| EXPECT_INT_ZERO(test_prob_sampler(0.1, 0.001)); |
| |
| htracer_free(g_test_tracer); |
| htrace_log_free(g_test_lg); |
| htrace_conf_free(g_test_conf); |
| return EXIT_SUCCESS; |
| } |
| |
| // vim: ts=4:sw=4:tw=79:et |