Yahoo did a study a while back and found that ~50% of their visitors had a cold ...

newman314 · on March 5, 2012

Plus if you access Twitter over SSL, there might not be caching resulting in heavy loads repeatedly.

ceejayoz · on March 5, 2012

I'd imagine Twitter's serving `Cache-Control: public` where appropriate.

newman314 · on March 5, 2012

You would think but sadly, no.

They serve the actual tweet as "Cache-Control: no-cache, no-store, must-revalidate, pre-check=0, post-check=0"

EDIT: Just to check, I also looked at one of their css resources. https://si0.twimg.com/a/1330626450/t1/css/t1_core_logged_out...

Cache-Control: private, max-age=31449600

So I'm not confident Twitter actually understands how to set things.

PS: Hey Twitter, I can help =)

eonwe · on March 5, 2012

Maybe it's just that they don't want that one page cached as they may update their scripts, images and stylesheets. And for that css-file, I think that whenever they change the css, they'll just give the resource a new address so cache is only invalidated when there are actual changes.

newman314 · on March 5, 2012

That does not make sense. If they update that page, then it'll get refreshed when it expires.

For the CSS file, some browsers are buggy so it really should be set to "Cache-Control: public".

See http://www.acunote.com/blog/2008/07/why-you-should-use-cache...

Zirro · on March 5, 2012

In early 2007. Isn't this likely to have changed in five years?

burgerbrain · on March 5, 2012

http://samsaffron.com/archive/2012/02/17/stop-paying-your-jq...

Apparently Stack Overflow sees similar numbers.

pyre · on March 6, 2012

I wouldn't call 20% "similar" to 50%, but it is still a significant number.