X-mas/NY present to SWI-Prolog development

The main development machine is nearly 7 years old. The Amsterdam VU has moved to a new building where this good old machine looks a bit out of place. I’m looking for a (commercial) user willing to sponsor a new development desktop. I’m thinking of an approx. 2000 euro budget for a desktop based on an AMD 3900X with 64Gb memory and 1TB M2 ssd. In-kind is of course possible and if is more practical that you remain the owner, that is fine. You get a mention on the contributors page in return (next to bug fixes and cool features as always).

Please respond by personal message on Discourse or by mail.


It took some time. Thanks to DataChemist I can now use a flashy AMD 3950X with 16 cores/32 threads and 64Gb memory to develop SWI-Prolog!

It compiles SWI-Prolog with all default packages in 19 sec elapsed time! The cores and memory are great for testing serious applications and running VMs to test for other platforms.

Thanks DataChemist!


I’m curious what command(s) you’re benchmarking. On my 2-year-old 4-CPU (4 threads) 3.4GHz 16GB machine with SSD, it takes 85 sec (200 sec user, 20 sec system) to run ninja clean; ninja.

My results are indeed using time ninja after ninja clean. The build includes all packages in complete standard config (cmake -G Ninja .. with all prerequisites and all submodules installed).

To me this seems much in line with expectations. Theoretically 32 threads could do the job 8 times faster or on a little over 10 seconds. But, you are already not getting full resource usage (220/4 = 55 sec) with 4 threads. Using more threads this gets worse as some parts of the build need to be done before anything else and others after (almost) all other tasks. Hyperthreads are slower than the real thing, so the 32 core is (very rough estimate as the efficiency of hyperthreading depends a lot on the workload) probably more like 24. I’d also be surprised if I/O and memory are not getting bottlenecks. Compilation is very I/O intensive.

Modern CPUs don’t seem to differ that much. The AMD 3950X runs my Prolog single threaded benchmark about 25% faster than the old Intel i7-3770 (4 cores, 8 threads). That almost 8 year old machine took 95 sec, although that was only on the second run. The first run was more like 2 min as the disk was really slow. M2 SSD could have saved the machine, but don’t fit in the old motherboard, so end up with a long chain of outdated components that needs updating and 8 years seems close to end-of-life.

The biggest CPU improvement is from 4 to 16 cores with a rise of TPD from 77 to 105W.
I wonder how power usage in idle state compares.

With DataChemist’s contribution I should be fine for another 8 years :slight_smile: