Kafka Log Compaction not starting

To have compaction running you need to have at least 2 segment files (one finished and one running).

according to your configuration

log.segment.bytes=1073741824
log.segment.bytes=536870912

(please check why you have two identical properties).

You need to have one file 512Mb full so kafka can run compaction on it. Please check that you have at least 2 segment files for topic-partition you want to be compacted

As Natalia said, we can log.segment.bytes config determines the log segment file roll by size.

If you don't want to change the log.segment.bytes (or) you don't want to wait till the log segment reaches its full size, you can use log.segment.ms config to roll the log segment file by time and trigger compaction.