Slow Performance - any idea why?

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dillonjamescole
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Joined: Fri Nov 29, 2019 11:07 pm

Slow Performance - any idea why?

Post by dillonjamescole » Fri Nov 29, 2019 11:17 pm

I'm running 2.14.13 on a 2018 15" MacBook Pro with a 2.6 Ghz 6-core i7 and getting painfully slow transcode speeds after the progress bar hits about 15%. Any idea why?

My source file is a 2048x858 ProRes 422 LT file going into a 2K scope container at 100 Mbit/s. I have the number of threads DCP-o-matic should use set to 6 (there are 12 threads total on my machine. I'm not running any other intensive programs. My only thought is the drive I'm transcoding to is bottlenecking the whole process.

Thanks for any advice!

carl
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Re: Slow Performance - any idea why?

Post by carl » Fri Nov 29, 2019 11:24 pm

What drive are you transcoding to?

dillonjamescole
Posts: 3
Joined: Fri Nov 29, 2019 11:07 pm

Re: Slow Performance - any idea why?

Post by dillonjamescole » Fri Nov 29, 2019 11:44 pm

Hey, Carl. Thanks for your reply. I ran this same transcode but swapped out my dinky SanDisk USB-C flash drive with a Samsung T5 and it completed about 6x faster. My suspicion about the drive was correct. Sorry for jumping the gun on asking for help!

carl
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Re: Slow Performance - any idea why?

Post by carl » Fri Nov 29, 2019 11:47 pm

No worries, I'm glad you got to the bottom of it!

Carsten
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Location: Germany

Re: Slow Performance - any idea why?

Post by Carsten » Sat Nov 30, 2019 1:15 am

Was that really a usb flash drive? They can be painfully slow when writing.

You should set your number of threads to 12. It will speed up considerably. I also think, unless space is a constraint, you should set your encoding data rate to 150MBIt/s.

- Carsten

dillonjamescole
Posts: 3
Joined: Fri Nov 29, 2019 11:07 pm

Re: Slow Performance - any idea why?

Post by dillonjamescole » Sat Nov 30, 2019 3:48 am

Okay, thank you very much for the tips, Carsten!

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