[squid-dev] [PATCH] Drop deprecated MSIE Cache-Control pre-check/post-check

[Alex Rousskov]

On 01/26/2017 02:08 AM, Amos Jeffries wrote:
> These two options have been a bit of annoyance for a long time.
> Primarily because they are custom controls and almost all uses of them
> is the garbage '0' values that even MSIE ignores completely. Validating
> correctness would add processing which offsets the performance gained
> from ignoring them.
> 
> 
> It has come to my attention that the MSIE guys are now advising people
> not to use them. So it seems we can take advantage and make some
> performance gains on a lot of traffic, while helping to hasten their demise.
> 
> By adding these as registered CC values which are just dropped we can
> both reduce outbound bandwith by ~20 bytes per message and avoid all the
> slow String handling which CC_OTHER brings to the processing when these
> are the only non-standard options present.

-O

By default, Squid should not sanitize legitimate traffic that somebody
out there might depend on. "MSIE guys" recommendation is valuable but
does not apply to the default proxy behavior.

Huge performance gains might outweigh these "do not harm" concerns when
dealing with deprecated features, but no such gains have been
demonstrated (or are expected AFAICT) in this specific case.

Alex.