Pegasus3 R6 24TB – Hard Drive Noise Question:

[Noah Kadner]

Archiving how?

Noah

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[Ray Sherman]

Thanks for the reply……… I’m archiving off my SD card.

[Noah Kadner]

You mean you’re using FCPX to make a camera archive? I would suggest copying the card contents over first.

Noah

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[Ray Sherman]

Yes, I normally copy the entire SD card and keep it intact in a folder on an external hard drive. I then perform the following steps;
Open FCPX
Open the import window
Click on the hard drive that contains the folder
Highlight the folder
Create Archive

During the process of archiving, the Pegasus drives are noisy as they’re spinning. This is the only time they get noisy, the drives are quiet during playback. Thanks, ray

[Noah Kadner]

Hmm- you might actually want to submit feedback. Either your drives have an issue or you might just be hitting an FCPX bug. https://www.fcpworks.com/submitting-better-fcpx-feedback-to-apple/

Noah

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[Ray Sherman]

Actually, all I need to know if there is anybody else that has a noisy Promise Technology Pegasus raid array. All six drives seem to be quite noisy during the FCPX archiving. This has nothing to do with my MacBook Pro hard drive. Thanks, Ray

[Joe Marler]

[Ray Sherman] “all I need to know if there is anybody else that has a noisy Promise Technology Pegasus raid array. All six drives seem to be quite noisy during the FCPX archiving.”

If fed a certain pattern of IOs, a normally quiet drive (or RAID array) can become louder. For RAID this might be due to the IO size adversely interacting with the stripe size or segment size. Or if the IOs are random vs sequential it could cause lots of seeking or cache misses which translate into more physical IO. It is impossible to say which of those (if any) might be a factor in what you observe.

Examination with the terminal dtrace utilities shows the FCPX archiving process mostly does 2 and 4 megabyte reads from the media tree and 1 megabyte writes to the archive bundle. The block addresses indicate both are mostly sequential in nature.

When I create a large camera archive on my 32TB Thunderbay 4 RAID-0 array, it doesn’t make much noise. If you are using RAID-6, that has a dramatic write penalty vs RAID-0 or even RAID-5. Maybe it’s that combined with conflicting read and write streams on the same device.

[Ray Sherman]

Thanks for your input…….. I’m running in Raid 5. Other than archiving and/or file transferring, the drives are fairly quiet. Playback of 4K is 99% quiet, just a gurgle now and then. I don’t know anyone that has a Pegasus therefore, I don’t know if this is normal or not. Thanks again for explaining some thing that may be the cause. Ray