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jabooth
Sep 19, 2007, 04:31 PM
:confused:

OK, so if I encode a HD video using visualhub or render a DVD with iDVD surely I would expect both my Macbooks cores would be screaming at 100%, however checking them with activity monitor, they never do! It shows both operating around 70% - doesn't this mean I'm wasting some of the power of the macbook (30%!?!) I can't help think my encode could be done 30% faster...

Can anyone explain this?

Thanks,

Harry



stallion187
Sep 19, 2007, 04:45 PM
:confused:

OK, so if I encode a HD video using visualhub or render a DVD with iDVD surely I would expect both my Macbooks cores would be screaming at 100%, however checking them with activity monitor, they never do! It shows both operating around 70% - doesn't this mean I'm wasting some of the power of the macbook (30%!?!) I can't help think my encode could be done 30% faster...

Can anyone explain this?

Thanks,

Harry

For one, just because your CPU is utilzed only 70%, doesn't mean that if you used it 100% you would get a 30% return.

You would get 30% return in CPU functions, but encoding does not just involve the CPU.

velocityg4
Sep 19, 2007, 05:20 PM
You are probably getting bottlenecked by your hard drive. As the file is encoded that information is getting written to your hard drive. So if your CPU only reaches a 70% load then your hard drive has likely peaked in its write speed.

I use to run into this problem on my dual G5 with standard def video. Once I set up a RAID 0 array my storage was better able to keep pace with my CPU when compressing video in Final Cut.

jabooth
Sep 20, 2007, 01:46 AM
You are probably getting bottlenecked by your hard drive. As the file is encoded that information is getting written to your hard drive. So if your CPU only reaches a 70% load then your hard drive has likely peaked in its write speed.

I use to run into this problem on my dual G5 with standard def video. Once I set up a RAID 0 array my storage was better able to keep pace with my CPU when compressing video in Final Cut.

Logic told me it would be a bottleneck, but usually RAM is the problem (and having 2gigs of the stuff I presumed this was not the case).

Does anyone else believe Hard drive speed to be the issue? Any other macbook owners find similar findings?

Cheers

TheMonarch
Sep 20, 2007, 01:51 AM
Its the hardrive. Encoding a DVD, or iMovie project won't really use up more than a GB or ram, which all MBPs are equipped with.