Re: [Sks-devel] wserver_timeout value causing cascading failure?

[Phil Pennock]

On 2017-04-24 at 13:53 -0400, Jonathon Weiss wrote:
> An important note here is that I'm using Apache as a proxy for SKS (on
> 80, 443, and 11371).
> 
> If I understand how SKS works, it can accept and hold onto multiple
> client connections at once, but only processes them serially.

> 3) Any suggestions on what to do if/when wserver_timeout=1 becomes
>    insufficient?

The general model for tiered servers proxying connections is that each
server uses a timeout for the backend, or is given a timeout by the
backend, a little less than the timeout for the requests inbound to the
server.  "Tower of Hanoi Timeouts", per:

  https://medium.com/@liquidgecka/tower-of-hanoi-timeouts-c9476d96ca4b

That's based on an assumption of parallel handling by the backend; for
the SKS case, using ToHT along with making sure that the reverse proxy
only hands off one connection at a time should avoid the cascade.

Also: what does SKS do with multiple requests on one connection, does it
answer each, thus not getting around to requests on the next connection,
ever?

I haven't used Apache in some years, but from
https://httpd.apache.org/docs/trunk/mod/mod_proxy.html I think that you
want:

  ProxyPass "/pks" "http://localhost:11371/"; max=1 disablereuse=On

-Phil