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Slow Thunderbolt 3 Speeds

I am using a 15 inch 2016 MacBook Pro with 4 Thunderbolt 3 ports.

I have a 12 TB G-Technology G-Raid Thunderbolt 3 drive configured in Raid 0

if i do a speed test on the G-Raid drive via any one of the ports I’m only getting 222 mbps write and 235mbps read.

From the test I’ve seen on others on youtube etc, they are getting way faster speeds than me.

i wanted to know why this is happening, and to see if i can get the full speed as they seem to be.

i have tried testing with both the thunderbolt 3 cable that came with the G-Raid and also a Cable Matters 40 gbps thunderbolt 3 cable 0.5m.

the drive is 9.45 TB full of 12 TB

i have no other means of testing on another machine as this is the only one with thunderbolt 3.

Please help!

The main reason for lower performance will be from the amount of used space you have on the drive. It will drop once you start to fill it up.

With the 12TB with a RAID0 empty drive you will get high 300s and over 400MB as long as the drives are operating properly.

Did you change the format at all to be APFS or add encryption? both of those will lower its performance as well.

Hi, thanks for the reply.

the drive is formatted in Mac OS Extended (Journaled) no encryption.

good to know about the APFS though!

thanks for the info, i was worried my thunderbolt port wasn’t working properly. i couldn’t find any information anywhere to say if the drives slowed down as they filled up. all the reviews on youtube were of new and i assume empty drives, so when comparing them to mine, i saw a big difference.

Thanks again

Thom

Support for Western Digital Hard Drives | Western Digital

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