Jungtaek Lim created STORM-872:
----------------------------------
Summary: Expose interfaces to give users opportunity to customize
"executor" heartbeat module
Key: STORM-872
URL: https://issues.apache.org/jira/browse/STORM-872
Project: Apache Storm
Issue Type: Improvement
Reporter: Jungtaek Lim
I have seen many papers and slides addressing heartbeat timeout, and most of
these point out ZK is the reason.
- Storm@Twitter, SIGMOD 2014 :
http://db.cs.berkeley.edu/cs286/papers/storm-sigmod2014.pdf
- Scaling Storm, Hadoop Summit 2015 :
https://github.com/revans2/storm-presentations/blob/master/Haddop_Summit_2015_Scaling_Storm.pptx
- and so on.
ZK has a hard limit of throughput and reading / writing disk is the matter.
Throughput would be far more better when we're dealing worker heartbeat with
in-memory storage directly, or heartbeat daemon which can scale well.
(Trade-off could be made.)
If we can open the interface of worker heartbeat module, and give users
opportunities to customize it, it would be really great.
- Why I'm narrowing heartbeat to "worker" only?
-- I was thinking "supervisor" heartbeat too, but it uses ephemeral node of ZK,
which is normally not supported to other storage.
-- And in Scaling Storm, p15, about 99.2% of ZK workload is worker heartbeats.
I think ZK can take care of supervisor heartbeat without problem.
--- default of "supervisor.heartbeat.frequency.secs" is 5
--- default of "task.heartbeat.frequency.secs" is 3
--- I didn't mention "worker to supervisor" heartbeat cause it uses local file
system.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
