JUst upgraded my (Fedora 37) install to DT4.4 which came out over holidays. I have quickly opened it to verify it “works” by opening some past edits and all looks well. I also benchmarked it as I do for any new kernel and/or DT version using the phoronics benchmarks (with the inspiring foto’s of bench.SRW, masskrug.NEF and server_room.NEF – I have been doing this since DT 3.2.1 (using kernel 5.8.13).
Conclusion: DT 4.4 runs ~60% slower on the ‘bench’ image, but 6-13% faster on the other two benchmark images. Now … these benchmarks and images are not too representative of today’s processing (images are 18-24 Mpix, all use display referred), but a comparison using my own test image (42 Mpx, developed with Filmic also shows close to 10% longer execution time (I have included this as of DT 4.01 / kernel 6.0.11). All of this benchmarking is on current Fedora versions (not necessarily the same over this time interval), w/o significant background activity and take averages over 20 runs after discarding the 2 slowest and fastest as outliers. Hardware has been the same – i3-8100 with 8 or 16 Gb RAM and using SSD to load images from and RAM to write them to…
No, on the contrary – up here the new version is much faster.
dt 3.2 (in August 2020) ran for 2.785/8.373 seconds
dt 4.4.1 (now) ran for 1.532/3.807 seconds
(with openCL/without).
Naturally, the Nvidia drivers were not the same, neither were the linux kernels.
Thanks for the responses. To clarify (and respond to sugarbravo): my comparison was between 4.2.0 and 4.4.0; comparing with 3.2.1 indeed shows a massive improvement: 3.2.1 took 66-72 s whereas 4.4.0 takes 39s. The values for the versions in between were 59, 37, 35, 34, 34 (3.4, 3.6, 3.8, 4.0, 4.2). @hannoschwalm: I will do some digging (and asking at Fedora) whether build options have changed.
I will continue the benchmarking with new kernel versions coming out (typically once a week) and when 4.4.1 drops (4.4.0. only became available 2 weeks ago).
The data shows you are right, but I did not know that when starting (more triggered by the then new spectre/meltdown vulnerabilities which triggered me to compare with/without; short version: 1-2% difference at most). I since run this out of habit, to have a larger baseline with changes like major version changes of my distribution or DT.
Lastly: I probably wasn’t fully awake when typing the first post – I am on Fedora 38 (for both versions); I have in the meantime als verified that DT4.40. was built with gcc 13.1.1; DT4.2.1 was built with 13.0.1. The search continues (at a low priority as I found another much more annoying issue)