Nginx configuration to log datetime, bytes sent and total request time for cowboy performance monitoring on local server. Also ignores a bunch of static file types to keep the logs clean.

Nginx Performance Logging Hack

    map $request $loggable {
        ~*\.css|\.js|\.png|\.woff 0;
        default 1;
    }
    log_format slim '[$time_local] - $body_bytes_sent - $request_time - "$request" $status';
    include       bcore/local-nginx-default;
    include       mime.types;
    default_type  application/octet-stream;
    access_log  /path/to/access.log slim if=$loggable;