iMac G5 as fast as new SR 2.4 Ghz MB Pro? This can't be right.

[Scallywag]

I just got a new 2.4 Ghz Santa Rosa MacBook Pro (2 GB RAM). I wanted to compare SVCD (ffmpeg) encoding performance compared to my iMac G5 (2.0 Ghz, 1 GB RAM). The MB Pro with dual cores was only 5 minutes faster at encoding a 700 MB AVI to SVCD using the ffmpeg preset.

The dual cores obviously conferred no benefit whatsoever. If anything, the 5 minute difference was due to the 1 GB RAM difference.

Shouldn't the Intel Mac blow the doors off the iMac G5, especially with the dual cores?

[tomlee59]

You don't automatically get a speedup by going to multiple cores. The software has to be written to take advantage of the added resources. And not all tasks are easily subdivided in a way that allows for multiple cores to work on them. In this particular case, the particular encoder option you selected clearly doesn't make use of the extra core. Mpeg2enc has this option, so you may want to use it. In general, take a look at all the options for whatever encoder you are using, just to make sure you've selected all the performance-enhancing options that are available.

[exekutive]

I also have a Core Duo MBP and I've tried using the dual core threading under the options tab for mpeg2enc, and I haven't found it to make a noticeable difference.

[tomlee59]

Hmmm...maybe the option only works for pre-Intel Macs? Inquiring minds want to know...

[exekutive]

Actually that makes sense, because the option really says "Dual CPU", and not dual core CPU.