Let`s just say, IDV likes to eat the ram for breakfast and I find myself
frequently hitting the ceiling!!
Yes, RAM breakfast is our favorite meal of the day :-)
We have a user guide page on performance tuning which includes ways to
address memory usage:
http://www.unidata.ucar.edu/software/idv/docs/userguide/misc/PerformanceTuning.html
One of our focus areas in the coming months will be memory usage.
In general, there are trade offs between the level of interactivity and
the memory usage. e.g.,
being able to interactively probe the data, do cross sections, etc.,
tends to require the data to be
resident in memory. As the docs above describe you can set the data size
thresholds where we do not
keep the data in memory but rather cache it to disk when not needed (at
least for grids). This of
course does not work well with interactivity but does keep memory usage low.
Likewise, as Tom described, you can choose a single level for grids.
This keeps memory usage low but if you
switch levels we have to go re-read the data.
For a variety of reasons we take a big hit when dealing with imagery.
While we work on this one thing you can do is to specify
a lower image size resolution.
-Jeff