I'm currently running spark structured streaming application written in python(pyspark) where my source is kafka topic and sink i mongodb. I changed my checkpoint to Amazon EFS, which is distributed on all spark workers and after that I got increased I/o wait, averaging 8%
Currently I have 6000 messages coming to kafka every second, and I get every once in a while a WARN message:
22/02/25 13:12:31 WARN HDFSBackedStateStoreProvider: Error cleaning up files for HDFSStateStoreProvider[id = (op=0,part=90),dir = file:/mnt/efs_max_io/spark/state/0/90] java.lang.NumberFormatException: For input string: ""
I'm not quite sure if that message has anything to do with high I/O wait and is this behavior expected, or something to be concerned about?