private void scheduleGroupMetadataExpiration() {
        timer.schedule(
            GROUP_EXPIRATION_KEY,
            config.offsetsRetentionCheckIntervalMs(),
            TimeUnit.MILLISECONDS,
            true,
            config.offsetsRetentionCheckIntervalMs(),
            this::cleanupGroupMetadata
        );
    }
Schedule the group/offsets expiration job. If any exceptions are thrown above, the timer will retry.
group-coordinator/src/main/java/org/apache/kafka/coordinator/group/GroupCoordinatorShard.java