OT: why are LAMP sites slow?

[Paul Rubin]

aurora <aurora00 at gmail.com> writes:
> I'm lost. So what do you compares against when you said LAMP is slow?
> What  is the reference point? Is it just a general observation that
> slashdot is  slower than we like it to be?

Yes, that's the basic observation, not specifically Slashdot but for
lots of LAMP sites (some PHPBB sites are other examples) have the same
behavior.  You send a url and the server has to grind for quite a
while coming up with the page, even though it's pretty obvious what
kinds of dynamic stuff it needs to find.  Just taking a naive approach
with no databases but just doing everything with in-memory structures
(better not ever crash!) would make me expect a radically faster site.
For a site like Slashdot, which gets maybe 10 MB of comments a day,
keeping them all in RAM isn't excessive.  (You'd also dump them
serially to a log file, no seeking or index overhead as this happened.
On server restart you'd just read the log file back into ram).

> If you mean MySQL or SQL database in general is slow, there are truth
> in  it. The best thing about SQL database is concurrent access,
> transactional  semantics and versatile querying. Turns out a lot of
> application can  really live without that. If you can rearchitect the
> application using  flat files instead of database it can often be a
> big bloom.

This is the kind of answer I had in mind.

> A lot of these is just implementation. Find the right tool and the
> right design for the job. I still don't see a case that LAMP based
> solution is inherently slow.

I don't mean LAMP is inherently slow, I just mean that a lot of
existing LAMP sites are observably slow.