net/http: re-enable test

Now with a bit more paranoia and lower number of requests
to keep it under the default OS X 256 fd limit.

R=golang-dev, dsymonds, rsc
CC=golang-dev
https://golang.org/cl/5659051

diff --git a/src/pkg/net/http/transport_test.go b/src/pkg/net/http/transport_test.go
index a68a4d7225ac756890b7f9bf3823f923cf47dc0a..a36571a44468ce7c08ce9d58201e95bc939d6f14 100644 (file)
--- a/src/pkg/net/http/transport_test.go
+++ b/src/pkg/net/http/transport_test.go
@@ -635,9 +635,6 @@ func TestTransportGzipRecursive(t *testing.T) {
 
 // tests that persistent goroutine connections shut down when no longer desired.
 func TestTransportPersistConnLeak(t *testing.T) {
-       t.Logf("test is buggy - appears to leak fds")
-       return
-
        gotReqCh := make(chan bool)
        unblockCh := make(chan bool)
        ts := httptest.NewServer(HandlerFunc(func(w ResponseWriter, r *Request) {
@@ -653,12 +650,17 @@ func TestTransportPersistConnLeak(t *testing.T) {
 
        n0 := runtime.Goroutines()
 
-       const numReq = 100
+       const numReq = 25
        didReqCh := make(chan bool)
        for i := 0; i < numReq; i++ {
                go func() {
-                       c.Get(ts.URL)
+                       res, err := c.Get(ts.URL)
                        didReqCh <- true
+                       if err != nil {
+                               t.Errorf("client fetch error: %v", err)
+                               return
+                       }
+                       res.Body.Close()
                }()
        }
 
@@ -679,6 +681,7 @@ func TestTransportPersistConnLeak(t *testing.T) {
                <-didReqCh
        }
 
+       tr.CloseIdleConnections()
        time.Sleep(100 * time.Millisecond)
        runtime.GC()
        runtime.GC() // even more.
@@ -686,13 +689,11 @@ func TestTransportPersistConnLeak(t *testing.T) {
 
        growth := nfinal - n0
 
-       // We expect 5 extra goroutines, empirically. That number is at least
-       // DefaultMaxIdleConnsPerHost * 2 (one reader goroutine, one writer),
-       // and something else.
-       expectedGoroutineGrowth := DefaultMaxIdleConnsPerHost*2 + 1
-
-       if int(growth) > expectedGoroutineGrowth*2 {
-               t.Errorf("goroutine growth: %d -> %d -> %d (delta: %d)", n0, nhigh, nfinal, growth)
+       // We expect 0 or 1 extra goroutine, empirically.  Allow up to 5.
+       // Previously we were leaking one per numReq.
+       t.Logf("goroutine growth: %d -> %d -> %d (delta: %d)", n0, nhigh, nfinal, growth)
+       if int(growth) > 5 {
+               t.Error("too many new goroutines")
        }
 }