Kafka sink can be stucked if downstream is overload

[hicqu]

What did you do?

Run a changefeed task to sink to downstream Kafka.

What did you expect to see?

No response

What did you see instead?

If the downstream is overload, Kafka producer may be stucked forever.

Versions of the cluster

Upstream TiDB cluster version (execute SELECT tidb_version(); in a MySQL client):

(paste TiDB cluster version here)

Upstream TiKV version (execute tikv-server --version):

(paste TiKV version here)

TiCDC version (execute cdc version):

(paste TiCDC version here)

[hicqu]

I think it's caused by IBM/sarama#2823.