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diff --git a/src/test/common/Throttle.cc b/src/test/common/Throttle.cc
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+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2013 Cloudwatt <libre.licensing@cloudwatt.com>
+ *
+ * Author: Loic Dachary <loic@dachary.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program 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 Library Public License for more details.
+ *
+ */
+
+#include <stdio.h>
+#include <signal.h>
+
+#include <chrono>
+#include <list>
+#include <mutex>
+#include <random>
+#include <thread>
+
+#include "gtest/gtest.h"
+#include "common/Thread.h"
+#include "common/Throttle.h"
+#include "common/ceph_argparse.h"
+
+class ThrottleTest : public ::testing::Test {
+protected:
+
+ class Thread_get : public Thread {
+ public:
+ Throttle &throttle;
+ int64_t count;
+ bool waited = false;
+
+ Thread_get(Throttle& _throttle, int64_t _count) :
+ throttle(_throttle), count(_count) {}
+
+ void *entry() override {
+ usleep(5);
+ waited = throttle.get(count);
+ throttle.put(count);
+ return nullptr;
+ }
+ };
+};
+
+TEST_F(ThrottleTest, Throttle) {
+ int64_t throttle_max = 10;
+ Throttle throttle(g_ceph_context, "throttle", throttle_max);
+ ASSERT_EQ(throttle.get_max(), throttle_max);
+ ASSERT_EQ(throttle.get_current(), 0);
+}
+
+TEST_F(ThrottleTest, take) {
+ int64_t throttle_max = 10;
+ Throttle throttle(g_ceph_context, "throttle", throttle_max);
+ ASSERT_EQ(throttle.take(throttle_max), throttle_max);
+ ASSERT_EQ(throttle.take(throttle_max), throttle_max * 2);
+}
+
+TEST_F(ThrottleTest, get) {
+ int64_t throttle_max = 10;
+ Throttle throttle(g_ceph_context, "throttle");
+
+ // test increasing max from 0 to throttle_max
+ {
+ ASSERT_FALSE(throttle.get(throttle_max, throttle_max));
+ ASSERT_EQ(throttle.get_max(), throttle_max);
+ ASSERT_EQ(throttle.put(throttle_max), 0);
+ }
+
+ ASSERT_FALSE(throttle.get(5));
+ ASSERT_EQ(throttle.put(5), 0);
+
+ ASSERT_FALSE(throttle.get(throttle_max));
+ ASSERT_FALSE(throttle.get_or_fail(1));
+ ASSERT_FALSE(throttle.get(1, throttle_max + 1));
+ ASSERT_EQ(throttle.put(throttle_max + 1), 0);
+ ASSERT_FALSE(throttle.get(0, throttle_max));
+ ASSERT_FALSE(throttle.get(throttle_max));
+ ASSERT_FALSE(throttle.get_or_fail(1));
+ ASSERT_EQ(throttle.put(throttle_max), 0);
+
+ useconds_t delay = 1;
+
+ bool waited;
+
+ do {
+ cout << "Trying (1) with delay " << delay << "us\n";
+
+ ASSERT_FALSE(throttle.get(throttle_max));
+ ASSERT_FALSE(throttle.get_or_fail(throttle_max));
+
+ Thread_get t(throttle, 7);
+ t.create("t_throttle_1");
+ usleep(delay);
+ ASSERT_EQ(throttle.put(throttle_max), 0);
+ t.join();
+
+ if (!(waited = t.waited))
+ delay *= 2;
+ } while(!waited);
+
+ delay = 1;
+ do {
+ cout << "Trying (2) with delay " << delay << "us\n";
+
+ ASSERT_FALSE(throttle.get(throttle_max / 2));
+ ASSERT_FALSE(throttle.get_or_fail(throttle_max));
+
+ Thread_get t(throttle, throttle_max);
+ t.create("t_throttle_2");
+ usleep(delay);
+
+ Thread_get u(throttle, 1);
+ u.create("u_throttle_2");
+ usleep(delay);
+
+ throttle.put(throttle_max / 2);
+
+ t.join();
+ u.join();
+
+ if (!(waited = t.waited && u.waited))
+ delay *= 2;
+ } while(!waited);
+
+}
+
+TEST_F(ThrottleTest, get_or_fail) {
+ {
+ Throttle throttle(g_ceph_context, "throttle");
+
+ ASSERT_TRUE(throttle.get_or_fail(5));
+ ASSERT_TRUE(throttle.get_or_fail(5));
+ }
+
+ {
+ int64_t throttle_max = 10;
+ Throttle throttle(g_ceph_context, "throttle", throttle_max);
+
+ ASSERT_TRUE(throttle.get_or_fail(throttle_max));
+ ASSERT_EQ(throttle.put(throttle_max), 0);
+
+ ASSERT_TRUE(throttle.get_or_fail(throttle_max * 2));
+ ASSERT_FALSE(throttle.get_or_fail(1));
+ ASSERT_FALSE(throttle.get_or_fail(throttle_max * 2));
+ ASSERT_EQ(throttle.put(throttle_max * 2), 0);
+
+ ASSERT_TRUE(throttle.get_or_fail(throttle_max));
+ ASSERT_FALSE(throttle.get_or_fail(1));
+ ASSERT_EQ(throttle.put(throttle_max), 0);
+ }
+}
+
+TEST_F(ThrottleTest, wait) {
+ int64_t throttle_max = 10;
+ Throttle throttle(g_ceph_context, "throttle");
+
+ // test increasing max from 0 to throttle_max
+ {
+ ASSERT_FALSE(throttle.wait(throttle_max));
+ ASSERT_EQ(throttle.get_max(), throttle_max);
+ }
+
+ useconds_t delay = 1;
+
+ bool waited;
+
+ do {
+ cout << "Trying (3) with delay " << delay << "us\n";
+
+ ASSERT_FALSE(throttle.get(throttle_max / 2));
+ ASSERT_FALSE(throttle.get_or_fail(throttle_max));
+
+ Thread_get t(throttle, throttle_max);
+ t.create("t_throttle_3");
+ usleep(delay);
+
+ //
+ // Throttle::_reset_max(int64_t m) used to contain a test
+ // that blocked the following statement, only if
+ // the argument was greater than throttle_max.
+ // Although a value lower than throttle_max would cover
+ // the same code in _reset_max, the throttle_max * 100
+ // value is left here to demonstrate that the problem
+ // has been solved.
+ //
+ throttle.wait(throttle_max * 100);
+ usleep(delay);
+ t.join();
+ ASSERT_EQ(throttle.get_current(), throttle_max / 2);
+
+ if (!(waited = t.waited)) {
+ delay *= 2;
+ // undo the changes we made
+ throttle.put(throttle_max / 2);
+ throttle.wait(throttle_max);
+ }
+ } while(!waited);
+}
+
+std::pair<double, std::chrono::duration<double> > test_backoff(
+ double low_threshhold,
+ double high_threshhold,
+ double expected_throughput,
+ double high_multiple,
+ double max_multiple,
+ uint64_t max,
+ double put_delay_per_count,
+ unsigned getters,
+ unsigned putters)
+{
+ std::mutex l;
+ std::condition_variable c;
+ uint64_t total = 0;
+ std::list<uint64_t> in_queue;
+ bool stop_getters = false;
+ bool stop_putters = false;
+
+ auto wait_time = std::chrono::duration<double>(0);
+ uint64_t waits = 0;
+
+ uint64_t total_observed_total = 0;
+ uint64_t total_observations = 0;
+
+ BackoffThrottle throttle(g_ceph_context, "backoff_throttle_test", 5);
+ bool valid = throttle.set_params(
+ low_threshhold,
+ high_threshhold,
+ expected_throughput,
+ high_multiple,
+ max_multiple,
+ max,
+ 0);
+ ceph_assert(valid);
+
+ auto getter = [&]() {
+ std::random_device rd;
+ std::mt19937 gen(rd());
+ std::uniform_int_distribution<> dis(0, 10);
+
+ std::unique_lock<std::mutex> g(l);
+ while (!stop_getters) {
+ g.unlock();
+
+ uint64_t to_get = dis(gen);
+ auto waited = throttle.get(to_get);
+
+ g.lock();
+ wait_time += waited;
+ waits += to_get;
+ total += to_get;
+ in_queue.push_back(to_get);
+ c.notify_one();
+ }
+ };
+
+ auto putter = [&]() {
+ std::unique_lock<std::mutex> g(l);
+ while (!stop_putters || !in_queue.empty()) {
+ if (in_queue.empty()) {
+ c.wait(g);
+ continue;
+ }
+
+ uint64_t c = in_queue.front();
+
+ total_observed_total += total;
+ total_observations++;
+ in_queue.pop_front();
+ ceph_assert(total <= max);
+
+ g.unlock();
+ std::this_thread::sleep_for(
+ c * std::chrono::duration<double>(put_delay_per_count*putters));
+ g.lock();
+
+ total -= c;
+ throttle.put(c);
+ }
+ };
+
+ vector<std::thread> gts(getters);
+ for (auto &&i: gts) i = std::thread(getter);
+
+ vector<std::thread> pts(putters);
+ for (auto &&i: pts) i = std::thread(putter);
+
+ std::this_thread::sleep_for(std::chrono::duration<double>(5));
+ {
+ std::unique_lock<std::mutex> g(l);
+ stop_getters = true;
+ c.notify_all();
+ }
+ for (auto &&i: gts) i.join();
+ gts.clear();
+
+ {
+ std::unique_lock<std::mutex> g(l);
+ stop_putters = true;
+ c.notify_all();
+ }
+ for (auto &&i: pts) i.join();
+ pts.clear();
+
+ return make_pair(
+ ((double)total_observed_total)/((double)total_observations),
+ wait_time / waits);
+}
+
+TEST(BackoffThrottle, undersaturated)
+{
+ auto results = test_backoff(
+ 0.4,
+ 0.6,
+ 1000,
+ 2,
+ 10,
+ 100,
+ 0.0001,
+ 3,
+ 6);
+ ASSERT_LT(results.first, 45);
+ ASSERT_GT(results.first, 35);
+ ASSERT_LT(results.second.count(), 0.0002);
+ ASSERT_GT(results.second.count(), 0.00005);
+}
+
+TEST(BackoffThrottle, balanced)
+{
+ auto results = test_backoff(
+ 0.4,
+ 0.6,
+ 1000,
+ 2,
+ 10,
+ 100,
+ 0.001,
+ 7,
+ 2);
+ ASSERT_LT(results.first, 60);
+ ASSERT_GT(results.first, 40);
+ ASSERT_LT(results.second.count(), 0.002);
+ ASSERT_GT(results.second.count(), 0.0005);
+}
+
+TEST(BackoffThrottle, oversaturated)
+{
+ auto results = test_backoff(
+ 0.4,
+ 0.6,
+ 10000000,
+ 2,
+ 10,
+ 100,
+ 0.001,
+ 1,
+ 3);
+ ASSERT_LT(results.first, 101);
+ ASSERT_GT(results.first, 85);
+ ASSERT_LT(results.second.count(), 0.002);
+ ASSERT_GT(results.second.count(), 0.0005);
+}
+
+/*
+ * Local Variables:
+ * compile-command: "cd ../.. ;
+ * make unittest_throttle ;
+ * ./unittest_throttle # --gtest_filter=ThrottleTest.take \
+ * --log-to-stderr=true --debug-filestore=20
+ * "
+ * End:
+ */
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-11 01:49:27 +0000