mccaugh@uiucdcsb.cs.uiuc.edu (12/13/87)
I was intrigued by your remark that your "number-crunching" runs 100 times slower on a SUN than on a Symbolics, and wa just curious to know if 1) your SUN lacked a numeric co-processor assist; 2) the Symbolics benefited from similar assists. -- Thank you. Scott (mccaugh@uiucmsl)
dzzr@beta.UUCP (Douglas J Roberts) (12/15/87)
In article <168700008@uiucdcsb>, mccaugh@uiucdcsb.cs.uiuc.edu writes: > > I was intrigued by your remark that your "number-crunching" runs 100 times > slower on a SUN than on a Symbolics, and wa just curious to know if > 1) your SUN lacked a numeric co-processor assist; > 2) the Symbolics benefited from similar assists. > We have also run comparisons between Symbolics and Suns. We have a large discrete event simulation running on top of KEE (Knowledge Engineering Environment) that was developed on Symbolics hardware (an old, upgraded 3600 with an IFU). There is a fair amount of floating-point computation as well as a lot of symbolic computation in this application. When we loaded up the application on a Sun 3/260 we found that it ran ~1.2 times slower (80% as fast) as it did on the Symbolics. I was therefore surprised that someone else had noticed a 100-fold speed difference in LISPs between the two machines. We found that the Sun run-time was very sensitive to the paging space and the application memory image size. If either of these was too small, the application would garbage-collect itself into the ground. Perhaps this was a contributing factor to the above-mentioned 100-fold speed difference. --Doug -- --------------------------------------------------------------- Doug Roberts dzzr@lanl.gov ---------------------------------------------------------------