> According to our previous discussion, pg_basebackup is not depend on any of the postgresql configuration parameters. If I go for gzip format we need to compromise on time.
You do not necessarily compromise on time when compressing. Actually, a speed gain compared to uncompressed is possible. The better data is being compressed the less has to be written on (slow) disk. However, it comes with a CPU load penalty. I suggest you experiment with setups. Maybe --compress is doing still well with respect to compression rate but consumes considerably less CPU time.