Hi James,
On 06/09/2015 03:59 PM, James Smith wrote:
In many cases it will only be a few packets anyway so won't actually
make that much difference!
The point is that it is better to stop the request in the first place
by setting the appropriate expires/cache control header... than use
the etag mechanism...
In case it wasn't clear, we very much agree on this one, my question was
centered on the ETag in particular.
Thanks for your reply!
James
On 09/06/2015 14:56, Frederik Nosi wrote:
Hi James,
On 06/09/2015 02:36 PM, James Smith wrote:
Yes - it is the request over head - the client will still make the
request at which point the server has got to decide has it changed
before even - which for most static requests is the heaviest
(slowest) part before returning the not-changed response - and then
serving the content!
But at this point the server in case of a positive match will send
just a 304 reply with no content, thus saving bandwith and time (due
to eventual roundtrips) no?
You are better to:
(a) set near future or mid future headers [ expires in a month or in
a year]
Sure, the best request is the one that does not even come :-)
(b) alter filenames if you significantly change the file contents [
we use MD5 of content for js/css ]
This only if you're in the posisition to decide the site layout though.
Note this is "hyper-tuning" of Apache... some people may want to
enable it - it was originally set up when most users were on
28K/33.6K modems (or slower) and the transfer of data was the slow
part of the equation!
James
[...]
Thanks,
Frederik
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