Are all available cores being utilized by PI-C?

[Nocturnal]

Hello,

I'm considering building a new PC. Quad core CPUs are becoming quite affordable now and lots of software exploits them. In my current tool-set most notably the excellent DeepSkyStacker grabs every available CPU. How does PI-C deal with multiple cores? If it's a single thread/process program then it would be better to buy a faster (higher clock speed) dual core CPU instead.

I intend to run Windows XP or Vista if I can't avoid it.

I searched the forum and 'quad core' occured only once, in a Spanish thread that I don't think answered this question. If I missed the thread, please direct the way

Thanks,

   Sander

[Carlos Milovic]

Hi Sander

Yes, PI supports multithread processes, i.e. makes use of multiple cores. This is true for image rendition, color management and many processing modules. The later have to be specifically designed with multithread instructions, so there are a few that have not been optimized yed, and of course, we cannot guarantee that third party modules will complain this.

By the way, take a look at the "Global Preferences". Under the "Parallel Processing and Threads" category you'll find some controls over PI's behavior with multiple cores. For example, you may choose how many processors to use.

[Nocturnal]

Hi Carlos,

thanks for your reply, great news. I realize I could have found this out by installing the demo on my Centrino Duo or Pentium D computer but I'm not ready yet to start my 30 day eval so I figured I'd ask

I understand that you don't have control over 3rd party plugins but I would buy PI for what it comes with out of the box, plugins are a secondary concern. With the dominance of multi core CPUs and steady growth of image sizes and processing complexity I sure hope that folks who take the time to develop PI-C code will also consider multi-threading.

Best,

  Sander

[Juan Conejero]

Hi Sander,

As Carlos has said, PixInsight will use all logical processors available (or less if you specify so in global preferences). All processing modules where multithreading makes sense are fully parallelized now, except a few ones of minor importance (as NoiseGenerator for example).

If you are considering a new machine for image processing (along with other processor and memory-intensive tasks), I recommend you a quad-core processor at least, and a 64-bit operating system. The new PixInsight 1.2, due for release in a few days, introduces the first 64-bit versions of PixInsight for both Linux and Windows platforms. Consider also a minimum of 8 GB of RAM, which are also quite affordable now. All of these things make a really big difference in performance.

Cheers,

Juan

[Nocturnal]

Hi Juan,

I would probably go for a multi boot system with 64 bit windows and a 32 bit flavor as well. Maybe I'll linux up as well although I generally have no need for it.

Thanks,

  Sander