[ODE] Parallelizing ODE?

[Russ Smith]

> How large is a "large connected system"? 500 bodies? More?

it's the joints that slow you down. i tend to think of a system
with a 500x500 matrix (say, 166 B&S joints) as 'large', since beyond
that it gets hard to do real-time simulation with O(n^3) techniques.

note that parallelizable sparse matrix techniques are a big win only
for very large matrices. typically these techniques are optimized for,
e.g. 10000x10000 problems. there may not be a huge improvement
for a 500x500 matrix, with all the overheads involved. for a very
large system it is worth looking at other simulation techniques that
are faster in your particular problem domain. e.g., if you have a 
large tree structured system with no hard contacts then a reduced
coordinate simulator (e.g. dynamechs) is your best bet.

russ.

--
Russell Smith
http://www.q12.org