Flaky tests

[holiman]

Another round of flaky tests

• TestUDPv5_lookup log
• TestUDPv4_Lookup log
• TestEth2PrepareAndGetPayload log
  • api_test.go:225: invalid number of transactions 0 != 1

[holiman]

From the v4 log

[00:27:16]     v4_udp.go:525: TRACE[10-12|17:54:22.059] >> PING/v4                                id=fb701727441d6fd5 addr=127.0.255.7:5000 err=<nil>
[00:27:16]     v4_udp.go:576: TRACE[10-12|17:54:22.060] << PONG/v4                                id=fb701727441d6fd5 addr=127.0.255.7:5000 err="unsolicited reply"
[00:27:16]     v4_lookup_test.go:161: error mismatch: got "unsolicited reply", want %!q(<nil>)

That's odd. We send a PING, then when we get the PONG, we deem it unsolicited reply

[holiman]

The v4 lookup test can be reproed locally with the following little change, simulating a bit of lag in the loop which handles adding the reply matcher

diff --git a/p2p/discover/v4_udp.go b/p2p/discover/v4_udp.go
index 29ae5f2c08..228175f6c8 100644
--- a/p2p/discover/v4_udp.go
+++ b/p2p/discover/v4_udp.go
@@ -466,6 +466,7 @@ func (t *UDPv4) loop() {
 			return
 
 		case p := <-t.addReplyMatcher:
+			time.Sleep(200 * time.Millisecond)
 			p.deadline = time.Now().Add(respTimeout)
 			plist.PushBack(p)
 

[holiman]

I wonder if maybe the respTimeout is too small, at 500ms, but OTOH the logs says 17:54:22.059] >> PING/v4 and 17:54:22.060] << PONG/v4 - that's only 10ms elapsed, so should not be removed in-between.