Getting better perf from multithreaded app

[dargaud]

Hello all,
first post here,
I have a multithreaded program that I can't live without. It's a commercial RAW image conversion program called SilkyPix. It works fine under Wine, with a few very minor bugs. But one thing nags me: it's oh so slow...

- I have a 64bit quad core with Ubuntu 64.
- Wine can use the multicore (or so I've read in the FAQ).
- SilkyPix is also multicore-enabled (it ran very fast using all cores on that machine when I still had XP on it).
- But when I run SilkyPix in Wine it hardly uses one single processor.
- Indeed the cpufreq daemon hardly ever triggers from its lowest speed, so it goes 800MHz instead of 2600.
- I/Os stay very low (40Mb per image, one every 10s) so I don't think it's the issue.

So my question is: how can I get better performance on this one app ? Or does wine dedicate only one thread per application, even if the app itself is multithreaded ? XP was 5~10 times faster which is rather important when you need to process 1000 wedding pictures !

Thank you for clearing this up.

[DaVince]

- Indeed the cpufreq daemon hardly ever triggers from its lowest speed, so it goes 800MHz instead of 2600.

You could change your power governor to something like ondemand - sounds like it's set to conservative instead to me. There's also a "performance" governor which just maxes out CPU clocking.

You can set these power governors using:

Code: Select all

cpufreq-selector -g ondemand

Where you can replace ondemand with anything else, of course.

[dargaud]

Thanks for the advice, but the app still uses only one CPU. I should add that I've followed this and now have 1.1.29 on Jaunty.[/url]

[vitamin]

Thanks for the advice, but the app still uses only one CPU.

Wine might not properly reporting number of CPUs or the program doesn't detect it right under Wine. Try forcing it to use 4 threads if you can.

Wine won't dedicate individual threads to programs - it's left for system to take care of. Lots of things in Wine are single threaded still so you might not necessarily see all cores used 100%.