> nginx version: nginx-1.9.5 Have you tried updating to a newer version of nginx? The 1.9 branch is probably 5 years old... It looks like the code you mention has changed somewhat, though I don't know if it has any effect on $request_time. https://github.com/nginx/nginx/blob/60f648f035fa05667b9ccbbea1b3a60d83534d9a/src/http/v2/ngx_http_v2.c