[Zope-dev] Optimization and speed

[Stephan Richter]

Hello everyone,

I write this mail, because I could not find anything useful in the archives:

I have a pretty big site with quiet a big database (PostGreSQL) in the 
background. When a site loads I can tell that after about 5 seconds the 
site is ready to download. The site downloads quickly thereafter if I am on 
a T1, DSL or Cable Modem connection. But since most of our users have 28.8k 
and 56k modem connection, we have to optimize for them too.
When accessing the site over a modem, it takes a long time to load the site 
and then it pops up all at once (in IE (AOL) and Netscape). Is there a way 
that I can send parts of the HTML as it is generated, so that the customer 
starts seeing information before the entire site is loaded. Our site is 
about 50% slower than our competitors sites (we are serving 62kB and the 
competitor has up to 203kB and is 50% faster!!!) which use PHP and 
ColdFusion. I know that Zope is not slower. I strongly believe it is the 
HTML output which is not optimized (we are going to speed up the DB 
connection very soon by dedicating a NIC only for the DB communication).

Technical Facts:
- Zope 2.1.6+PCGI+Apache - Virtual Hosts for HTTP and HTTPS
- PostGreSQL 7.0 (DB size: 50MB), ZPyGreSQLDA, UserDB
- ZODB threads: 4
- Web Server: Pentium 500, RH 6.1, 322MB RAM (not all used), 100 MBit NIC
- DB Server: Pentium 500, RH 6.1, 322MB RAM (plenty left to use), 100 MBit NIC
- dedicated subnet

If someone could give me some tips where I should start looking for speed 
holes, please let me know. Do you think it is the DB which could be so slow 
and I should cache search results more, are there ZServer/Apache options I 
can set or anything else in Zope I should have a look at?

Regards,
Stephan
--
Stephan Richter
CBU - Physics and Chemistry
Web2k - Web Design/Development & Technical Project Management