.
Thanks Eric. Stata tech support (thanks Kerry) had a similar answer.
Time to buy more memory I think.
"If you would like to get a good idea of when your system is beginning
to use
virtual memory with Stata then you should specify a very small swap file
(enough to contain everything currently running) and then when the
operating
system starts complaining about allocating RAM you will have reached
the limit.
Another method to try is to check the machine's hard drive light and
see if it
goes from the normal flicker to a steady light when you are performing
calculations in Stata."
Hi David:
Try increasing your memory incrementally using a program like the
one described here:
http://www.stata.com/statalist/archive/2009-07/msg00899.html
Try this with virtual memory turned ON and then try it again with it
turned OFF & look for any differences in both the -query- in Stata
as well as the memory usage reported in the Mac OSX 'Activity
Monitor.app' ( located here: "/Applications/Utilities/Activity\
Monitor.app" ) because Stata might think it has more memory
allocated than the system is really giving it. The reason for this
is that *nix systems have virtually unlimited swap file space & it
can also use mounted/storage/network drives or devices for swap
space in parallel. So, even if VM is turned off in Stata, the system
can readily use HD space for virtual memory AND if you've got an
external HD or mounted network drive, your system mightbe using that
to increase the memory that Stata can utilize.
You can try this process again after disabling the Mac OSX virtual
memory/swap space by editing your "/etc/rc" file (with caution):
1.typing into terminal: sudo pico /etc/rc 2. Type # in front of the
line : "dynamic_pager -F ${swapdir}/swapfile" 3. now type into
terminal: sudo srm /private/var/vm/swapfile*
But I would make a backup of your swapfile* before tinkering with
these settings (e.g. "sudo cp /etc/rc /etc/rc.orig" ).Another
suggestion might be to find or create a dataset larger than your
physical memory limits (4 GB) and ask Stata to open it--then take a
look at your -query- and your 'Activity Monitor.app' (that is, if
Stata will somehow open a file that large with VM turned off..)
Best, Eric
*
* 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/
