A Few Notes On HTTP
It’s How The Web Works, Stupid!
Pierre Phaneuf <pphaneuf@gmail.com>

HTTP is core
Regular web browser
AJAX
XML-RPC, SOAP
WebDAV, CalDAV, Subversion
Atom Publishing Protocol

Caching
We all know HTTP caching is important, like
flossing, and most of us leave it at that, like
flossing —— David Heinemeier Hansson
Set the Expires header
Use 301 instead of 302 when applicable

But My Site Is Dynamic!
Set the Last-Modified header
Set the ETag header
But beware!
Frameworks are silly sometimes
Clustering (inode numbers)

Compression
It’s easy.
It’s good.

Keep Alive
Friend or Foe?
Memory usage on the server
A reverse-proxy can help

AJAX
Increased load on servers?
Decrease the load, if done right!

Fastest way to handle a request
Not handling it!
Content distribution network

A Golden Age
Static content
CGI dynamic content
In-process dynamic content (Apache, ISAPI)
Out-of-process dynamic content (FastCGI,
WSGI)

Tools
Firebug’s Net tab
How long it took
What is cached
Dependencies
Wireshark (and tcpdump)

Questions?
Thank you!
Pierre Phaneuf <pphaneuf@gmail.com>