Re: General use of rewrite / redirect
| From: | Per Jessen | Date: | Wed, 19 Mar 2008 10:11:21 +0000 |
| Subject: | Re: General use of rewrite / redirect | ||
| References: | 1 2 3 4 5 6 | Groups: | php.general |
| Request: | Send a blank email to php-general+get-271774@lists.php.net to get a copy of this message | ||
Stut wrote:
> On 19 Mar 2008, at 09:54, Per Jessen wrote:
>>
>> BTW, why does the browser do this for objects it has already cached?
>> (assuming they're fresh/not expired)
>
> Because by default most web servers don't add expiry headers, so it's
> up to the browser.
My server does add expire headers - and I still see lots of 304s. I've
checked that the expiry information is correct.
> Adding expiry headers for certain content types is very easy in most
> web servers and depending on traffic patterns it can cause a very
> healthy drop in traffic.
> Combine that with a convention for new versions of the files as they
> get changed and you can put the expiry date a long time into the
> future. We use a year on all our images, css and js files and it's
> lead to a drop of ~40% in traffic to the static servers.
Same here - I am just wondering about the need for the conditional GET
then. What makes the browser want to revalidate an object when it has
a valid (=unexpired) copy cached?
/Per Jessen, Zürich