Performance impact while using stream-sts

[nihn]

Hello,

we use vts and sts nginx modules. Unfortunately we have experienced strange performance issues and after debugging it seems that sts module causes them.

We have couple of nginx which proxies all kind of traffic (tcp, udp, http) and on those which proxies much tcp/udp traffic and have sts module enabled we see big performance drop (even in http part). I am attaching one of our metric which shows how drastically upstream response drops when module is disabled:

It is worth noting that we haven't observed any visible impact when we disabled vts module, also this problem appears only during peak hours.

[ngocketit]

Any update on this? I'm planning to use these modules but then found this issue. Having a proper monitoring is crucial for a load balancer. Unfortunately, Nginx opensource sucks in this respect and we have to rely on third party modules. Really appreciate your work on this @vozlt.

[vozlt]

@nihn Thanks for reporting. I need detailed informations to confirm the problem. So I have some questions as follows:

1. What is the upstream response time measured by using?
   • $upstream_response_time in ngx_http_upstream_module
   • responseMsec in nginx-module-vts
   • ...
2. What is the type(http|stream) of upstream response time in the above graph?
   • upstream response time in http block
   • upstream response time in stream block
3. Have you checked the nginx error log at that time?
4. What you expect is nginx-module-vts is no problem and nginx-module-stream-sts is suspicious during peak hours, is right?
   • nginx-module-vts
     • on: NO PROBLEM
     • off: NO PROBLEM
   • nginx-module-stream-sts
     • on: PROBLEM
     • off: NO PROBLEM
5. How much traffic(requests/sec, bytes/sec) do you have during peak hours?
6. Please let me know your environment informations.
   • os
   • $ nginx -V output
   • nginx-module-vts version
   • nginx configurations

[nihn]

Hello voltz. I switched jobs I no longer work with Nginx. Maybe @psliwka can provide more details.

[psliwka]

@mlowicki, can you recall what this was about?