Hi all,
sorry for bothering, but we have noticed some differences in behavior
between 1.11 and 1.12 releases and need your help in understanding them.
First I would like to mention that we are running geode in Kubernetes.
We perform shutdown of the worker node that is hosting one member(e.g.
coordinator locator). Shutdown procedure affect member in a following way:
1. TCP shared unordered connections towards other members are terminated
2. Member receives graceful shut-down indication and starts with the
shut-down procedure
Usually connections starting to be terminated first and the shut-down
indication comes short after (e.g. ~10 milliseconds in difference). The
step 1. triggers availability check towards the other members for which
TCP connection has been previously lost. At this point of time
coordinator is unaware of ongoing shut-down and assumes that all other
members are actually having issues due to connection loss. Even after
coordinator receives the graceful shut-down indication this process of
availability check is not stopped. What happens later on is that
availability check fail for all members and coordinator initiates their
removal with RemoveMemberMessage. This message is succesfully received
on the other members forcing them to shut-down.
In geode 1.11 everything is same except the fact that availability check
pass and therefore removals aren't initiated.
In logs it can be seen that for both releases TCP availability check
fail, but HeartbeatMessageRequest/HearbeatMessage check fails only on
1.12 and pass on 1.11. In 1.12 release it can be seen that heartbeat
request and heartbeat messages are sent but does not reach their
destination members. RemoveMemberMessage which are sent later on reach
their destination successfully. Does anybody know what was changed in
1.12 that could lead to such difference in behavior?
Additionally, availability check is not stopped when graceful shutdown
is initiated. Do you think that this could be improved, so that member
stops ongoing availability check when detects gracefull shutdown? Just
to add that shutdown procedure is also delayed due to unsuccessful
attempts to estabilsh TCP connections towards the other members.
BRs,
Jakov
