How much better are 64 but platforms

[Bill Moran]

Hey,

I've never used FreeBSD on a 64 bit platform, and with a recent project I've got
a client asking me, "How much faster would this run if we put it on an Itanium."

So, in the future, I'll probably be getting a 64 bit machine to try this out on.

But it got me thinking, what should I _expect_ to see in improvement?  This
application is mostly comparing strings, there are no 64 bit integers or floats
to be obvious bottlenecks on a 32 bit platform, so (lacking actual experience)
how much can I expect the application to speed up if I move it to a 64 bit
platform?

I understand that nobody can answer this question exactly, but I'm curious to
hear people's experiences.  I mean, if you just took FreeBSD (for example) by
itself and moved it from 32 - 64 bit, how much faster is it (assuming the same
mhz processor, if possible).  How about PostgreSQL (which is the database
server we're using).

In general, how much faster is C compiled on a 64 bit platform?  Basically, all
this app does is pull a crapload of database records into RAM, do a whole bunch
of string comparisons, generate some percentages, and write significant results
back to another database table.  Should I expect 64 bit to be a big improvement?

Any thoughts or experience would be welcome.  Thanks in advance.

-- 
Bill Moran
Potential Technologies
http://www.potentialtech.com