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On Linux I would usually use "hdparm -tT device" when I want a quick idea of how an hard drive is performing compared to another; having switched to Mac OS X a few months back I have yet to find something similar and as easy to use.

I have read that diskutil can do similar things on Mac but I am not clear about how I should use it to do something similar to the hdparm command above.

Any ideas on how to do this or on alternatives? Thanks!

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You probably don't need to benchmark it, all Apple users will tell you that its performing GREAT either way ;) – pauska Oct 2 '10 at 13:27

Some tools I use:

I'm sure there are others I"m not thinking of at the moment. My current favorite is probably DIskfire. I would also check out the Xsanity forums, because they're experts at OS X disk performance, especially in Xsan.

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The latter 2 are dead links and the 1st one seems last updated in 2006 and doesnt work on external USB drives in Mac OS 10.9. – Syclone0044 Nov 12 '15 at 11:22

(bear in mind I never used Mac CLI so there can be little differences from what I write)

you could try dd:

dd if=/dev/sda of=/dev/zero bs=4096 count=10240 iflag=direct

This will copy 40MiB of data from the beginning of the drive and show you the average speed.

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I wouldn't trust this -- in my experience, OS X's version of dd seems to move data much slower than the devices are capable of. – Gordon Davisson Oct 3 '10 at 6:00
The Mac version of dd doesn't have the iflag command line argument. – e40 Feb 20 '14 at 19:48

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