Re: [PATCH] Do not send unretriable requests on reused pinned connections

On 12/01/2012 06:02 PM, Alex Rousskov wrote:
> To summarize, our choices for a pinned connection created for the
> current client are:
>
> Before sending the request:
>
> 1. Reopen and repin used pconns to send unretriable requests,
> just like non-pinned connection code does. This eliminates
> HTTP pconn race conditions for unretriable requests. This is
> what the proposed patch does for SslBump.
>
> 2. Send all requests without reopening the pinned connection.
> If we encounter an HTTP pconn race condition, see below.
>
>
> After the request, if an HTTP pconn race happens:
>
> 0. Send an error message to the client.
> This is what we do today and it breaks things.
>
> 1. Reset the client connection.
> Pretend to be a dumb tunnel.
>
> 2. Retry, just like the current non-pinned connection code does.
> This is what the proposed patch implements.
>
>
> Current code does 2+0. That does not work.
>
> The proposed patch does 1+2. That works in my limited tests.
>
> Henrik suggested 2+1. I agree that it is also an option worth
> considering.

I am leaning towards implementing 2+1 _and_ removing the current
connection repinning code as not needed.

We could leave repinning code in case it is needed later to fix broken
clients, but no such clients are known at this time, while that code is
complex and requires fixes (the patch posted here earlier), so I am
leaning towards removing it completely for now. With some effort it can
be re-introduced at a later time, of course.

If there are any better ideas, please let me know.

Thank you,

Alex.
Received on Tue Dec 04 2012 - 20:19:09 MST