diff --git a/src/pkg/net/fd_bsd.go b/src/pkg/net/fd_bsd.go
index 4f5dd6e524a..8bb1ae53847 100644
--- a/src/pkg/net/fd_bsd.go
+++ b/src/pkg/net/fd_bsd.go
@@ -33,6 +33,8 @@ func newpollster() (p *pollster, err error) {
 	return p, nil
 }
 
+// First return value is whether the pollServer should be woken up.
+// This version always returns false.
 func (p *pollster) AddFD(fd int, mode int, repeat bool) (bool, error) {
 	// pollServer is locked.
 
@@ -64,7 +66,9 @@ func (p *pollster) AddFD(fd int, mode int, repeat bool) (bool, error) {
 	return false, nil
 }
 
-func (p *pollster) DelFD(fd int, mode int) {
+// Return value is whether the pollServer should be woken up.
+// This version always returns false.
+func (p *pollster) DelFD(fd int, mode int) bool {
 	// pollServer is locked.
 
 	var kmode int
@@ -77,6 +81,7 @@ func (p *pollster) DelFD(fd int, mode int) {
 	// EV_DELETE - delete event from kqueue list
 	syscall.SetKevent(ev, fd, kmode, syscall.EV_DELETE)
 	syscall.Kevent(p.kq, p.kbuf[:], nil, nil)
+	return false
 }
 
 func (p *pollster) WaitFD(s *pollServer, nsec int64) (fd int, mode int, err error) {
diff --git a/src/pkg/net/fd_darwin.go b/src/pkg/net/fd_darwin.go
index 3dd33edc205..382465ba667 100644
--- a/src/pkg/net/fd_darwin.go
+++ b/src/pkg/net/fd_darwin.go
@@ -32,6 +32,8 @@ func newpollster() (p *pollster, err error) {
 	return p, nil
 }
 
+// First return value is whether the pollServer should be woken up.
+// This version always returns false.
 func (p *pollster) AddFD(fd int, mode int, repeat bool) (bool, error) {
 	// pollServer is locked.
 
@@ -65,7 +67,9 @@ func (p *pollster) AddFD(fd int, mode int, repeat bool) (bool, error) {
 	return false, nil
 }
 
-func (p *pollster) DelFD(fd int, mode int) {
+// Return value is whether the pollServer should be woken up.
+// This version always returns false.
+func (p *pollster) DelFD(fd int, mode int) bool {
 	// pollServer is locked.
 
 	var kmode int
@@ -80,6 +84,7 @@ func (p *pollster) DelFD(fd int, mode int) {
 	//	rather than waiting for real event
 	syscall.SetKevent(ev, fd, kmode, syscall.EV_DELETE|syscall.EV_RECEIPT)
 	syscall.Kevent(p.kq, p.kbuf[0:], p.kbuf[0:], nil)
+	return false
 }
 
 func (p *pollster) WaitFD(s *pollServer, nsec int64) (fd int, mode int, err error) {
diff --git a/src/pkg/net/fd_linux.go b/src/pkg/net/fd_linux.go
index 085e423072a..03679196d99 100644
--- a/src/pkg/net/fd_linux.go
+++ b/src/pkg/net/fd_linux.go
@@ -51,6 +51,8 @@ func newpollster() (p *pollster, err error) {
 	return p, nil
 }
 
+// First return value is whether the pollServer should be woken up.
+// This version always returns false.
 func (p *pollster) AddFD(fd int, mode int, repeat bool) (bool, error) {
 	// pollServer is locked.
 
@@ -114,7 +116,9 @@ func (p *pollster) StopWaiting(fd int, bits uint) {
 	}
 }
 
-func (p *pollster) DelFD(fd int, mode int) {
+// Return value is whether the pollServer should be woken up.
+// This version always returns false.
+func (p *pollster) DelFD(fd int, mode int) bool {
 	// pollServer is locked.
 
 	if mode == 'r' {
@@ -133,6 +137,7 @@ func (p *pollster) DelFD(fd int, mode int) {
 			i++
 		}
 	}
+	return false
 }
 
 func (p *pollster) WaitFD(s *pollServer, nsec int64) (fd int, mode int, err error) {
diff --git a/src/pkg/net/fd_unix.go b/src/pkg/net/fd_unix.go
index e9d2e4165f1..a97674267c5 100644
--- a/src/pkg/net/fd_unix.go
+++ b/src/pkg/net/fd_unix.go
@@ -109,17 +109,24 @@ func (s *pollServer) AddFD(fd *netFD, mode int) error {
 // Evict evicts fd from the pending list, unblocking
 // any I/O running on fd.  The caller must have locked
 // pollserver.
-func (s *pollServer) Evict(fd *netFD) {
+// Return value is whether the pollServer should be woken up.
+func (s *pollServer) Evict(fd *netFD) bool {
+	doWakeup := false
 	if s.pending[fd.sysfd<<1] == fd {
 		s.WakeFD(fd, 'r', errClosing)
-		s.poll.DelFD(fd.sysfd, 'r')
+		if s.poll.DelFD(fd.sysfd, 'r') {
+			doWakeup = true
+		}
 		delete(s.pending, fd.sysfd<<1)
 	}
 	if s.pending[fd.sysfd<<1|1] == fd {
 		s.WakeFD(fd, 'w', errClosing)
-		s.poll.DelFD(fd.sysfd, 'w')
+		if s.poll.DelFD(fd.sysfd, 'w') {
+			doWakeup = true
+		}
 		delete(s.pending, fd.sysfd<<1|1)
 	}
+	return doWakeup
 }
 
 var wakeupbuf [1]byte
@@ -386,9 +393,12 @@ func (fd *netFD) Close() error {
 	// the final decref will close fd.sysfd.  This should happen
 	// fairly quickly, since all the I/O is non-blocking, and any
 	// attempts to block in the pollserver will return errClosing.
-	fd.pollServer.Evict(fd)
+	doWakeup := fd.pollServer.Evict(fd)
 	fd.pollServer.Unlock()
 	fd.decref()
+	if doWakeup {
+		fd.pollServer.Wakeup()
+	}
 	return nil
 }