Hi Navneeth

If you wrap redis as a state backend, you cannot easily share data across slots 
as Flink construct state backend per operator with local thread only.

If you use a redis cluster as a externalized service to store your data, you 
can share data across slots easily. However, compared with the reduced cost of 
serialization, the introduce of network communicate cannot be ignored. There 
exists trade-off here, and we cannot ensure there would be a performance gain. 
Actually, I prefer the time used in CPU serialization is much less than the 
time consumed through the network.

Best
Yun Tang
________________________________
From: Navneeth Krishnan <reachnavnee...@gmail.com>
Sent: Wednesday, January 8, 2020 12:33
To: user <user@flink.apache.org>
Subject: Using redis cache in flink

Hi All,

I want to use redis as near far cache to store data which are common across 
slots i.e. share data across slots. This data is required for processing every 
single message and it's better to store in a in memory cache backed by redis 
rather than rocksdb since it has to be serialized for every single get call. Do 
you guys think this is good solution or is there any other better solution? 
Also, Is there any reference on how I can create a centralized near far cache 
since the job and operators are distributed by the job manager.

Thanks

Reply via email to