Generated upstreams are missing upstream zone size

[kate-osborn]

A/C:

• Each upstream should specify an upstream zone size: http://nginx.org/en/docs/http/ngx_http_upstream_module.html#zone

[kate-osborn]

@pleshakov what's a good default zone size? 256k?

[brianehlert]

@pleshakov what's a good default zone size? 256k?

I believe that NIC is now 512 to handle additional N+ metrics if you want to forward proof.

[pleshakov]

@kate-osborn I suggest trying to experiment -- see which value will fail for X number of upstream servers during reload. If it is still not clear, better to ask on NGINX community channels.

[jasonwilliams14]

@pleshakov @brianehlert @kate-osborn
Hopefully this is helpful. Accounts for the extra added HTTP codes R25 added.

nginx/kubernetes-ingress#2009

[kate-osborn]

Upstream zone size testing on Nginx 1.23

Zone Size	Max Upstream Servers
256k	312
512k	648
1m	1311

I think 512k is a reasonable default. Thoughts @pleshakov @brianehlert @jasonwilliams14?