net/rpc: log Call reply discard

It means serious user error that can lead to
hard to debug issues under load, log entry
will not harm.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5574075

diff --git a/src/pkg/net/rpc/client.go b/src/pkg/net/rpc/client.go
index 6fb414e089cdeb9b25d0e00a8b0e85138af9019a..abc1e59cd510858c66b3c70ff33c7a9a2af09957 100644 (file)
--- a/src/pkg/net/rpc/client.go
+++ b/src/pkg/net/rpc/client.go
@@ -145,6 +145,7 @@ func (call *Call) done() {
        default:
                // We don't want to block here.  It is the caller's responsibility to make
                // sure the channel has enough buffer space. See comment in Go().
+               log.Println("rpc: discarding Call reply due to insufficient Done chan capacity")
        }
 }