For some reason i got this message second time. Here is fixed patch: https://lists.tarantool.org/pipermail/tarantool-patches/2019-October/012162.html
Guess it could be lost due to updated subject.

среда, 30 октября 2019г., 17:03 +03:00 от Konstantin Osipov kostja.osipov@gmail.com:

* Ilya Kosarev <i.kosarev@tarantool.org> [19/10/29 19:59]:
> join_vclock test could fail on huge load due to vclock advance
> comparing to an actual WAL. In order to fix this we updated wal_sync so
> that now we can obtain up to date vclock on the flushed state using it.
> It is also better to get max index and index count in single request in
> join_vclock test. With fixes mentioned above it is not fragile anymore.

 I suggest we copy vclock. it's not a good idea to make the two
 threads depend on each other on memory. the relay thread may be
 cancelled while the messasge is in the wal thread.


--
Konstantin Osipov, Moscow, Russia