precision of responseMsec

[jingyuan66]

Hello!
The precision of responseMsec is too small, and the response time is too short, resulting in a response time of 0ms. Is there any way to change this?

[u5surf]

@jingyuan66 Hi, Thanks submit the issue. Unfortunately the upstream responseMsec has been depended by nginx upstream module, its precision cannot change any way from this module.
https://github.com/nginx/nginx/blob/f45c2707ea1bf6fde3bd0c045cc4a63cdc4a966a/src/http/ngx_http_upstream.c#L5796-L5804

[jingyuan66]

Thank you for the quick response and the information on the fixed precision of the nginx upstream module for response times.
I also want to explore another way to obtain the response time data. I considering using following prometheus query:
sum(rate(nginx_vts_upstream_response_seconds_total[1m])) by (backend) * 1000 / sum(rate(nginx_vts_upstream_requests_total[1m])) by (backend)
this query calculates the average response time in milliseconds for each backend by summing the response times and dividing by request count over the past minute. Would this effectively provide the precision I need?
Thank you again for your help!