Sun/Moon positions are easy calculations.

The database thing will be the slowdown. If he's using PERL, the usual database to use is SQL. I don't know how fast/efficient it is, though. My uses have been limited to it's use by things like my blog. I have no direct interaction, though.

His hardware will also be important. My newest drives are 2TB SATA with 3.0Gb/s transfer rates and 64Mb cache (not even top of the line). I have noticed that once I have a file opened in my programs, subsequent transactions are all but instantaneous. I've moved 10's of megs from disk to memory and back in seconds or less.

Finally, and I don't know how PERL handles this, but I can load data into memory simply by placing it into arrays. Once that is done then I'm just dealing with CPU to RAM transactions. Again, don't know about PERL, but in XBasic I am limited only by available system resources, which under WinXP being 32 bit is 2 gigs per process. Oh, and arrays are dynamic meaning I can declare X[1000, 1000, 1000] and it won't take up any memory (except the pointer*) until I start putting in values.

*Oh, pointers are fun... :)

Brian