OT: why are LAMP sites slow?

[Dave Brueck]

Paul Rubin wrote:
> How would you go about building such a site?  Is LAMP really the right
> approach?

Two major problems I've noticed, don't know if they are universal, but they sure 
hurt the performance:

1) Some sites have not put any thought into caching - i.e. the application 
server is serving up images or every single page is dynamically generated even 
though all (or most) of it is static such that most of the requests just aren't 
cacheable.

2) Because a database is there, it gets used, even when it shouldn't, and it 
often gets used poorly - bad or no connection pooling, many trips to the 
database for each page generated, no table indices, bizarro database schemas.

Overall I'd say my first guess is that too much is being generated on the fly, 
often because it's just easier not to worry about cacheability, but a good web 
cache can provide orders of magnitude improvement in performance, so it's worth 
some extra thought.

One project we had involved the users navigating through a big set of data, 
narrowing down the set by making choices about different variables. At any point 
it would display the choices that had been made, the remaining choices, and the 
top few hits in the data set. We initially thought all the pages would have to 
be dynamically generated, but then we realized that each page really represented 
a distinct and finite state, so we went ahead and built the site with Zope + 
Postgres, but made it so that the URLs were input to Zope and told what state to 
generate.

The upshot of all this is that we then just ran a web spider against Zope any 
time the data changed (once a week or so), and so the site ended up "feeling" 
pretty dynamic to a user but pretty much everything came straight out of a cache.

-Dave