From c1d742025caec62cf38cea1166fa6c4d0f7e207b Mon Sep 17 00:00:00 2001 From: John Newbery Date: Fri, 20 Apr 2018 15:45:31 -0400 Subject: [PATCH] [tests] Fix feature_block flakiness feature_block.py occasionally fails on Travis. I believe this is due to a a race condition when reconnecting to bitcoind after a subtest that expects disconnection. If the test runs ahead and sends the INV for the subsequent test before we've received the initial sync getheaders, then we may end up sending two headers messages - one as a response to the initial sync getheaders and one in response to the INV getheaders. If both of those headers fail validation with a DoS score of 50 or higher, then we'll unexpectedly be disconnected. There is only one validation failure that has a DoS score bewteen 50 and 100, which is high-hash. That's why the test is failing immediately after the "Reject a block with invalid work" subtest. Fix is to wait for the initial getheaders from the peer before we start populating our blockstore. That way we won't have any invalid headers to respond to it with. --- test/functional/feature_block.py | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/test/functional/feature_block.py b/test/functional/feature_block.py index 181c7f3369..38b76239e5 100755 --- a/test/functional/feature_block.py +++ b/test/functional/feature_block.py @@ -1306,7 +1306,13 @@ class FullBlockTest(BitcoinTestFramework): self.nodes[0].disconnect_p2ps() self.nodes[0].add_p2p_connection(P2PDataStore()) network_thread_start() - self.nodes[0].p2p.wait_for_verack() + # We need to wait for the initial getheaders from the peer before we + # start populating our blockstore. If we don't, then we may run ahead + # to the next subtest before we receive the getheaders. We'd then send + # an INV for the next block and receive two getheaders - one for the + # IBD and one for the INV. We'd respond to both and could get + # unexpectedly disconnected if the DoS score for that error is 50. + self.nodes[0].p2p.wait_for_getheaders(timeout=5) def sync_blocks(self, blocks, success=True, reject_code=None, reject_reason=None, request_block=True, reconnect=False, timeout=60): """Sends blocks to test node. Syncs and verifies that tip has advanced to most recent block.