Re: Multiplexing proxy gateway requests to backend servers

On Mon, 2002-08-19 at 09:00, Alex Rousskov wrote:
> On 19 Aug 2002, Ian Holsman wrote:
> 

Good .. thats fantastic news Alex.

The other thing to remember is that in >our< case (yours may vary)
connection setup/teardown may account for ~10ms, while the actual thing
being reversed proxied is a order of magnitude (or more) larger, and
this stuff just gets lost in the noise.

--Ian

> > I was thinking of doing something like this for quite some time. the
> > only issues I can see are keepalives.
> 
> There should be no problem with this approach as far as I know. Many
> proxies, including open-source Squid, maintain the client-side
> connection pool virtually independent from the server-side pool.
> 
> > 	* do they handle things like cookies per request or per
> > 	  connection?
> 
> Cookies are end-to-end things that are not related to hop-by-hop
> connection management.
> 
> > 	* authentication
> 
> Same here unless you are talking about some proprietary authentication
> methods that require certain connection reuse patterns (but those are
> usually not proxied anyway).
> 
> > 	* handling of keepalive timeouts might be tricky
> 
> Not in general, AFAIK. You just maintain two connection pools. The
> timeout and other algorithms are pretty much the same for each side.
> 
> > 	* ie.. do keepalives keep some state, I am never sure
> 
> Not sure what you mean by state here. There is no HTTP state, but,
> yes, since a connection may survive several HTTP transactions, there
> is some internal state to be kept (e.g., destination address, idle
> timer, etc.)
> 
> > there are also some other minor problems if you want to load balance the
> > backendservers, as that would break.
> 
> Yes, but load balancing needs special options and algorithms anyway.
> Most of them are not really closely related to idle connection
> management.
> 
> 
> $0.02,
> 
> Alex.
> 
> -- 
>                             | HTTP performance - Web Polygraph benchmark
> www.measurement-factory.com | HTTP compliance+ - Co-Advisor test suite
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-- 
Ian Holsman
Performance Measurement & Analysis
CNET Networks
PH: 415-344-2608