p

Chapter09/Cargo.toml

@@ -10,3 +10,23 @@ rand = "0.4.2"
 [[bin]]
 name = "performance_release_mode"
 path = "performance_release_mode.rs"
+
+[[bin]]
+name = "performance_omission1"
+path = "performance_omission1.rs"
+
+[[bin]]
+name = "performance_omission2"
+path = "performance_omission2.rs"
+
+[[bin]]
+name = "performance_profiling1"
+path = "performance_profiling1.rs"
+
+[[bin]]
+name = "performance_profiling2"
+path = "performance_profiling2.rs"
+
+[[bin]]
+name = "performance_profiling3"
+path = "performance_profiling3.rs"

Chapter09/performance_omission1.rs

@@ -0,0 +1,21 @@
+extern crate flame;
+use std::fs::File;
+
+fn main() {
+   let v: Vec<u64> = vec![2; 1000000];
+
+   flame::start("Iterator .collect");
+   let mut _z = vec![];
+   for _ in 0..1000 {
+      _z = v.iter().map(|x| x*x).collect::<Vec<u64>>();
+   }
+   flame::end("Iterator .collect");
+
+   flame::start("Iterator iterate");
+   for _ in 0..1000 {
+      v.iter().map(|x| x * x).for_each(drop);
+   }
+   flame::end("Iterator iterate");
+
+   flame::dump_html(&mut File::create("flame-graph.html").unwrap()).unwrap();
+}

Chapter09/performance_omission2.rs

@@ -0,0 +1,9 @@
+use std::mem::forget;
+
+fn main() {
+   for _ in 0..10000 {
+      let mut a = vec![2; 10000000];
+      a[2] = 2;
+      forget(a);
+   }
+}