Try to fix concurrency example

examples/concurrency.rs

@@ -18,6 +18,7 @@ extern crate futures_cpupool;
 
 use futures::Future;
 use futures_cpupool::{CpuFuture, CpuPool};
+use std::sync::Arc;
 use std::time::{Duration, Instant, SystemTime};
 use tarpc::future::{Connect};
 use tarpc::util::{FirstSocketAddr, Never, spawn_core};
@@ -46,20 +47,22 @@ impl FutureService for Server {
                 for i in 0..size {
                     vec.push((i % 1 << 8) as u8);
                 }
-                futures::finished::<_, Never>(vec)
+                futures::finished(vec)
             }))
     }
 }
 
-fn run_once<'a>(clients: &'a [FutureClient], concurrency: u32, print: bool)
-    -> Box<Future<Item=(), Error=()> + 'a>
+fn run_once(clients: Arc<Vec<FutureClient>>, concurrency: u32) -> Box<Future<Item=(), Error=()>>
 {
     let start = Instant::now();
     let futs = clients.iter()
+        .enumerate()
         .cycle()
+        .enumerate()
         .take(concurrency as usize)
-        .map(|client| {
+        .map(|(iteration, (client_id, client))| {
             let start = SystemTime::now();
+            debug!("Client {} reading (iteration {})...", client_id, iteration);
             let future = client.read(CHUNK_SIZE).map(move |_| start.elapsed().unwrap());
             future
         })
@@ -76,14 +79,12 @@ fn run_once<'a>(clients: &'a [FutureClient], concurrency: u32, print: bool)
         let min_latency = *latencies.iter().min().unwrap();
         let max_latency = *latencies.iter().max().unwrap();
 
-        if print {
-            println!("{} requests => Mean={}µs, Min={}µs, Max={}µs, Total={}µs",
-                     latencies.len(),
-                     mean.microseconds(),
-                     min_latency.microseconds(),
-                     max_latency.microseconds(),
-                     total_time.microseconds());
-        }
+        info!("{} requests => Mean={}µs, Min={}µs, Max={}µs, Total={}µs",
+                 latencies.len(),
+                 mean.microseconds(),
+                 min_latency.microseconds(),
+                 max_latency.microseconds(),
+                 total_time.microseconds());
     }).map_err(|e| panic!(e)))
 }
 
@@ -107,16 +108,16 @@ fn main() {
     let _ = env_logger::init();
 
     let server = Server::new().listen("localhost:0".first_socket_addr()).wait().unwrap();
-    println!("Server listening on {}.", server.local_addr());
+    info!("Server listening on {}.", server.local_addr());
 
     // The driver of the main future.
     let mut core = reactor::Core::new().unwrap();
 
-    let clients = (1...5)
+    let clients = (0..4)
         // Spin up a couple threads to drive the clients.
         .map(|i| (i, spawn_core()))
         .map(|(i, remote)| {
-            println!("Client {} connecting...", i);
+            info!("Client {} connecting...", i);
             FutureClient::connect_remotely(server.local_addr(), &remote)
                 .map_err(|e| panic!(e))
         })
@@ -124,9 +125,13 @@ fn main() {
         // because `futures::collect` iterates sequentially.
         .collect::<Vec<_>>();
 
-    let clients = core.run(futures::collect(clients)).unwrap();
-    println!("Starting...");
-    let runs = ::std::iter::once(run_once(&clients, MAX_CONCURRENCY, false))
-        .chain((1...MAX_CONCURRENCY).map(|concurrency| run_once(&clients, concurrency, true)));
-    core.run(futures::collect(runs)).unwrap();
+    let runs = futures::collect(clients).and_then(|clients| {
+        let clients = Arc::new(clients);
+        let runs = (1...MAX_CONCURRENCY)
+            .map(move |concurrency| run_once(clients.clone(), concurrency));
+        futures::collect(runs)
+    });
+
+    info!("Starting...");
+    core.run(runs).unwrap();
 }