Slow Speeds Due to Drive Encryption

If you enable drive encryption it will cause your file transfer speeds to drop from 80 mbs to 12mbs, quadrupling the time to a crawl and lock up the CPU at 100%.  USB to NAS with an encrypted drive will lock up your CPU and cause the drive to stop working

I have replaced cables and routers and return two unit.  Search the boards and found no answer.  

Hopefully this will help because it was a hassle.  

If you are using JBOD, you can encrypt one drive and leave the other drive as decrypted when formating.  

I ran this benchmark and only got 13 MB/s with encryption on and than turned it off and the CPU does not lock up at 100 percent.  

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Thank you for sharing this information.

It looks the encryption is being done at the software level and not hardware encryption. I know a couple of users complained about the CPU maxing at 100% with slow transfers and thought it was some thumbnail generating.  There is also heavy CPU use with USB to NAS transfers.    

Once you account for the speed difference, this thing is faster than my usb 3.0 drive.  

Most users don’t enable encryption…most of those who had CPU maxouts were having the issue not because of any encryption, which was disabled, but indeed because of the processes that builds the DLNA database and generates thumbnails. I wanted to point this out here, lest others read your post and start thinking incorrectly.