1 /*
2  * Copyright (c) Facebook, Inc. and its affiliates.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *     http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <folly/Benchmark.h>
18 #include <folly/io/async/EventBase.h>
19 #include <folly/portability/GFlags.h>
20 
21 using namespace folly;
22 
23 class CountedLoopCallback : public EventBase::LoopCallback {
24  public:
CountedLoopCallback(EventBase * eventBase,unsigned int count)25   CountedLoopCallback(EventBase* eventBase, unsigned int count)
26       : eventBase_(eventBase), count_(count) {}
27 
runLoopCallback()28   void runLoopCallback() noexcept override {
29     --count_;
30     if (count_ > 0) {
31       eventBase_->runInLoop(this);
32     }
33   }
34 
35  private:
36   EventBase* eventBase_;
37   unsigned int count_;
38 };
39 
BENCHMARK(timeMeasurementsOn,n)40 BENCHMARK(timeMeasurementsOn, n) {
41   EventBase eventBase;
42 
43   while (n--) {
44     CountedLoopCallback c(&eventBase, 10);
45     eventBase.runInLoop(&c);
46     eventBase.loop();
47   }
48 }
49 
BENCHMARK_RELATIVE(timeMeasurementsOff,n)50 BENCHMARK_RELATIVE(timeMeasurementsOff, n) {
51   EventBase eventBase(/* enableTimeMeasurement */ false);
52 
53   while (n--) {
54     CountedLoopCallback c(&eventBase, 10);
55     eventBase.runInLoop(&c);
56     eventBase.loop();
57   }
58 }
59 
60 /**
61  * --bm_min_iters=1000000
62  *
63  * ============================================================================
64  * folly/io/async/test/EventBaseBenchmark.cpp      relative  time/iter  iters/s
65  * ============================================================================
66  * timeMeasurementsOn                                           1.25us  798.33K
67  * timeMeasurementsOff                              214.47%   584.04ns    1.71M
68  * ============================================================================
69  */
70 
main(int argc,char ** argv)71 int main(int argc, char** argv) {
72   gflags::ParseCommandLineFlags(&argc, &argv, true);
73   runBenchmarks();
74 }
75