Fwd: [ module ] Add http upstream keep alive timeout parameter

[Maxim Dounin]

Hello!

On Fri, Jan 05, 2018 at 03:53:46PM +1100, Wei Xu wrote:

> Is it possible to merge the upstream keep alive feature first? because it's
> a valuable and simple patch.
> 
> We're using React server render, and by adding Nginx as the reverse proxy
> on each server, our AWS EC2 instances count reduced 25%, from 43 to 27-37
> C4.Large instances.
> 
> I wrote a detailed article to explain what happened and why it works at:
> https://theantway.com/2017/12/metrics-driven-development-how-did-i-reduced-aws-ec2-costs-to-27-and-improved-performance/
> 
> 
> The only problem now is we still using the custom patched version, which
> makes it *difficult to share the solution with other teams*. So back to the
> initial question, is it possible to merge this feature first, and you can
> create separate patches if you need to add more features later.

Sorry, but unlikely I'll be able to spend more time on this in the 
upcoming couple of weeks at least.  And I certainly don't want to 
commit incomplete solution, as keepalive_requests might be 
equally important for some workloads.

Meanwhile, you may want to consider solutions which do not require 
any patching, in particular:

- configuring upstream group and proxy_next_upstream 
  appropriately, so nginx will retry failed requests (this is the 
  default as long as you have more than one upstream server 
  configured and requests are idempotent);

- tuning your backend to use higher keepalive timeouts, which will 
  made the race unlikely.

-- 
Maxim Dounin
http://mdounin.ru/