[Gaul-devel] Storing large chromasomes with mmap

[Brian S. J. <br...@tu...>]

Hi, 

I'm currently using GAlib for an experiment I'm running just for
fun, but I might consider going with GAUL before I get too deep,
since I'm definitely not a C++ afficionado to put it mildly.  
(Too... much... context... must... run... home... to... Mom.)

This is sort of a heads-up don't-burn-the-bridge feature request.
I notice you're looking to make library structures opaque, which is
OK and generally a good move if sometimes done unnecessarily.  However, 
in my case and I can imagine in many others, I'm working with large 
genomes which would exhaust available swap memory if I kept all the 
populations loaded.  Thus I keep the chromasomes (the largest part) 
in a file on disk and mmap the file.  This has a few other 
advantages, like saving the chromasome allele states even on ungraceful 
program exit.

I'm still not done reading through GAUL code to see if this can be
safely handled, but as development progresses I'd encourage keeping
things in a state where at least the chromasome and the user's private data
area are not assumed to be malloced memory, and automated memory management
for those parts can be disabled.

Thanks.

PS. What I'm working on, just in case anyone would like to offer 
advice/comments is described here:

http://mojo.calyx.com/~bri/writings/decay.html

Though I've made more progress since writing that document and am
debating whether my concept of the way the GA process should work
as described there will really be a better fit for the problem than
one of the stock GA's with properly chosen parameters.

My main concern is that my solution space is much bigger than most
people seem to be using GA's for, though not as big as it may seem
since it may be relatively rich with desireable optimums.

--
Brian