[svn.haxx.se] · SVN Dev · SVN Users · SVN Org · TSVN Dev · TSVN Users · Subclipse Dev · Subclipse Users · this month's index

Re: [serf-dev] Re: [PATCH] Add a configuration option to disable HTTP pipelining.

From: Justin Erenkrantz <justin_at_erenkrantz.com>
Date: Thu, 21 Aug 2014 17:47:12 +0100

On Thu, Aug 21, 2014 at 5:30 PM, Lieven Govaerts <lgo_at_mobsol.be> wrote:
> Attached patch implements a slightly different approach but I think
> it's a valid workaround for the problem.

It may be useful to note why we register apps_ssl_info_callback in the
re-negotiate info callback. (It's because there can only be one

I'd also like to confirm whether we always re-init the SSL context
when we reset the connection - I think so, but didn't confirm...

> What it does is detect when a server triggers a renegotiation, and
> when that happens switch from a pipelined to a non-pipelined
> connection. It doesn't check if the application is actually using the
> pipelining, just if it's enabled or not.

As we discussed, this is the only thing that bothers me a bit - any
time we see a renegotiation, we'll reset the connection and try again
with pipelining turned off. I think we could do something to factor
in the state of serf's connection state - that is, something like
(conn->completed_requests - conn->completed_responses > 1) to not
reset the connection when there is only just the one pending response
that triggers the renegotiation. Ostensibly, after the renegotiation
succeeds, we *could* do pipelining again - we just can't handle
renegotiation when there is more than one outstanding request pending.

> I'm not convinced this completely removes the need for the
> "http-pipelining" option, because I'm not convinced this will cover
> all possible situations, but it should at least cover the ones
> reported to the serf dev list.

Agreed. But, I'm tempted to apply this patch and then see if we still
get real-world complaints before adding yet-another-knob. -- justin
Received on 2014-08-21 18:47:42 CEST

This is an archived mail posted to the Subversion Dev mailing list.

This site is subject to the Apache Privacy Policy and the Apache Public Forum Archive Policy.