How to decipher Firebug results in efforts to make site faster

Question

I am trying to fix my website and found this great tool called Firebug. I was trying to pinpoint why my website is really slow at loading (wordpress based website). I was hoping to see if anybody could give me some hints. The results that I get under Net->All is.

GET www.XXXXX.com  http://www.XXXXX.com/  302 Moved
Temporarily                   ?        10.08s
GET XXXXX.com           http://XXXXX.com/         200
OK                       XXXXX.com  9 KB   7.36s
GET submenucontents.htm?1232464334833
http://XXXXX.com/wp-content/themes/bl_custom/submenucontents.htm?1232464334833
200 OK XXXXX.com  878 B  442ms

3 requests

I first try to access the site with a www (and it redirects it to an address without the www prefix).

Under the response header for GET XXXXX.com I get:

Response Headers
Date    Tue, 20 Jan 2009 15:12:03 GMT
Server  Apache
Cache-Control no-store, no-cache, must-revalidate, post-check=0, pre-
check=0
Expires Thu, 19 Nov 1981 08:52:00 GMT
Pragma no-cache
X-Pingback http://XXXXX.com/xmlrpc.php
Set-Cookie xLanguage_7b770aac8932bb67100357a3682248c9=en; expires=Sat,
02-Jan-2010 20:32:09 GMT; path=/

Keep-Alive      timeout=15, max=100
Connection Keep-Alive
Transfer-Encoding       chunked
Content-Type    text/html; charset=UTF-8

Request Headers
Host XXXXX.com
User-Agent      Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.0.5)
Gecko/2008120122 Firefox/3.0.5
Accept  text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language en-us,en;q=0.5
Accept-Encoding gzip,deflate
Accept-Charset  ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive      300
Connection      keep-alive
Cookie  xLanguage_7b770aac8932bb67100357a3682248c9=en;
PHPSESSID=c8fde81fo6f76uitqemqk7k5b3

If anyone could help, it would be greatly appreciated!! Thank you.

Answer 1

Install YSlow and let it tell you what's wrong.

Answer 2

Use YSlow for Firebug

Also take a read of ACM Queue magazine's article High Performance Web Sites which is a well explained article on what you should do to design a fast client experience.

Answer 3

Ummm, if I'm reading that right, it took 10 seconds for your server to respond with a redirect. And another 7 seconds to spit out the main page. So it took 17 seconds to maybe see any content. Ouch.

You certainly should install YSlow as the other answers have suggested, but it's just going to tell you that your server (or your connection to it, or your DNS server[s], etc.) is going obscenely slow.

(Noting that the later request was much quicker, I'm going to guess DNS. If YSlow doesn't give any leads, a tool like Wireshark can show you the actual network traffic, so you can see what's taking so long.)

Answer 4

another good read is the stuff from Yahoo on high performance sites: link text and link text