From fd81069d72cdf91658f716c3377fcebbb9a52bce Mon Sep 17 00:00:00 2001
From: Hans Fugal <fugalh@fb.com>
Date: Thu, 2 Oct 2014 10:39:53 -0700
Subject: [PATCH] add some benchmarks
Summary: For great speed
Test Plan:
$ fbmake opt && _bin/folly/wangle/wangle-bench
============================================================================
folly/wangle/test/Benchmark.cpp relative time/iter iters/s
============================================================================
constantFuture 235.92ns 4.24M
promiseAndFuture 100.37% 235.04ns 4.25M
withThen 41.97% 562.17ns 1.78M
----------------------------------------------------------------------------
oneThen 539.03ns 1.86M
twoThens 64.01% 842.14ns 1.19M
fourThens 39.27% 1.37us 728.62K
hundredThens 1.82% 29.63us 33.75K
============================================================================
Reviewed By: davejwatson@fb.com
Subscribers: trunkagent, net-systems@, fugalh, exa, njormrod
FB internal diff: D1587871
---
folly/wangle/test/Benchmark.cpp | 79 +++++++++++++++++++++++++++++++++
1 file changed, 79 insertions(+)
create mode 100644 folly/wangle/test/Benchmark.cpp
diff --git a/folly/wangle/test/Benchmark.cpp b/folly/wangle/test/Benchmark.cpp
new file mode 100644
index 00000000..7d18db6b
--- /dev/null
+++ b/folly/wangle/test/Benchmark.cpp
@@ -0,0 +1,79 @@
+/*
+ * Copyright 2014 Facebook, Inc.
+ *
+ * Licensed 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 <folly/Benchmark.h>
+#include <folly/wangle/Future.h>
+#include <folly/wangle/Promise.h>
+
+using namespace folly::wangle;
+
+template <class T>
+T incr(Try<T>&& t) {
+ return t.value() + 1;
+}
+
+void someThens(size_t n) {
+ auto f = makeFuture<int>(42);
+ for (size_t i = 0; i < n; i++) {
+ f = f.then(incr<int>);
+ }
+}
+
+BENCHMARK(constantFuture) {
+ makeFuture(42);
+}
+
+// This shouldn't get too far below 100%
+BENCHMARK_RELATIVE(promiseAndFuture) {
+ Promise<int> p;
+ Future<int> f = p.getFuture();
+ p.setValue(42);
+ f.value();
+}
+
+// The higher the better. At the time of writing, it's only about 40% :(
+BENCHMARK_RELATIVE(withThen) {
+ Promise<int> p;
+ Future<int> f = p.getFuture().then(incr<int>);
+ p.setValue(42);
+ f.value();
+}
+
+// thens
+BENCHMARK_DRAW_LINE()
+
+BENCHMARK(oneThen) {
+ someThens(1);
+}
+
+// look for >= 50% relative
+BENCHMARK_RELATIVE(twoThens) {
+ someThens(2);
+}
+
+// look for >= 25% relative
+BENCHMARK_RELATIVE(fourThens) {
+ someThens(4);
+}
+
+// look for >= 1% relative
+BENCHMARK_RELATIVE(hundredThens) {
+ someThens(100);
+}
+
+int main() {
+ folly::runBenchmarks();
+}
--
2.34.1