st: -expand-, -expandcl-, and -set mem-; limit to the number of obs?

[Misha Spisok <misha.spisok@gmail.com>]

Hello, Statalist!

I have a few questions about Stata's ability to handle billions of observations.

On the Stata webpage, "Which Stata is right for me," it indicates that
the number of observations is unlimited for Stata versions other than
Small Stata.

The network computer I'm using has Stata 11.0 SE and claims to have
113,000MB of RAM available.  At one point I managed to set the memory
to 100g.  However, on subsequent tries (after logging out and logging
in), I get mixed results.  Sometimes I can only set the memory to 16g
(if I ask for more I get the "op. sys. refuses to provide memory"
message); sometimes I can get only 32g; and sometimes I can get 100g.
What could be the problem?

"Why am I asking for so much memory?", you might ask.  Well, I have a
data set that, when expanded, ought to give me about 2.63e+09 (i.e.,
nearly three billion) observations.  Whether I use -expand- or
-expandcl- I run into the same problem, getting the message "no room
to add more observations, etc."  I've compressed and dropped as much
as I can, but I still get this problem.  Am I asking too much of Stata
and/or "only" 113,000MB of RAM?  Is there a back-of-the-envelope way
to calculate how much RAM I would need to hold a given dataset?

Thank you for your time and attention.

Misha
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/