$upstream_response_time for logging

In my opinion, adding the upstream response time to the log output is a great help, finding bottlenecks for slow response times. So I changed my nginx.conf to this:

1log_format  main  '$remote_addr - $remote_user [$time_local] "$host" "$request" '
2                  '$status $body_bytes_sent "$http_referer" '
3                  '"$http_user_agent" "$http_x_forwarded_for" '
4                  '$upstream_response_time';

In my honest opinion, this should be set as default 🙂