Adding compressions can significantly reduce the size of the data transmitted.

Note: since compressions happens at run time it can add considerable processing overhead which can in turn cause negative performance.

        gzip on; #turns on compressions
        gzip_disable "msie6";
        gzip_vary on;
        gzip_proxied any;
        gzip_comp_level 6;
        gzip_buffers 16 8k;
        gzip_http_version 1.1;
        gzip_types text/plain text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript; #By default, NGINX compresses responses only with MIME type text/html

Has your compression been configured correctly?

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