FileVault disk encryption very slow.

Question

FileVault disk encryption very slow.

I have enabled FileVault. Last night, when I left my iMac, encryption had 8 hours to go. In the morning, it had 19 hours to go, and this afternoon, it has 16 hours remaining.

I believe that the iMac is going into sleep mode while encryption is in progress.

I have set Energy Saver to prevent automatic sleep when display is off.

Is there anything else I can do to prevent computer sleep from interrupting disk encryption or other apps when they are running.

iMac (Retina 5K, 27-inch, 2017), macOS High Sierra (10.13.2)

Posted on Jan 17, 2018 10:05 AM

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Answer 1

Top-ranking reply

sterling r

Community Specialist

Jan 19, 2018 7:58 AM in response to kingfisher500

Hello, kingfisher500.

It's my understanding that you want to know if there's any other power saving setting that needs to be adjusted to prevent the interruption of your File Vault. I may be able to help you with this. Make sure that the other setting to put the hard drive to sleep isn't on either. Other than that you should be good. This article is a good reference for: Energy Saving preferences

Also, File Vault encryption is going to take a long time regardless and should be able to run in the background: Use FileVault to encrypt the startup disk on your Mac

Encryption occurs in the background as you use your Mac, and only while your Mac is awake and plugged in to AC power. You can check progress in the FileVault section of Security & Privacy preferences. Any new files that you create are automatically encrypted as they are saved to your startup disk.

Let me know if this helps.

Thank you for using Apple Support Communities.

Cheers!

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Answer 2

Jan 19, 2018 7:58 AM in response to sterling r

Thanks for the reply. I have set the Energy Saving Preferences to prevent disk sleep, but the encryption process still seems incredibly slow. I suppose it will finish eventually.

I do not find the progress bar in the FileVault section to be reliable, and it takes a long time to settle down. Every time it begins with "More than a day" and then eventually comes down. Last evening, it said 8 hours remaining. Now, nearly 12 hours later, it says 6 hours remaining.

The Terminal command diskutil cs list | grep -e "Conversion" -e “diskname” gives a more meaningful report in terms of percent completed.

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Answer 3

Jan 19, 2018 9:53 AM in response to sterling r

Finally, what I can't understand is why the encryption is still not finished. I started on Tuesday evening. It is now Friday afternoon. So, FileVault encryption was the only thing running Tuesday, Wednesday, and Thursday nights.

I have a 3 TB Fusion drive with 2 TB of data, a 2017 iMac with a 4.2 GHz processor and 16 GB RAM.

Surely, it should be finished by now unless the drive or system goes to sleep in spite of the Energy Saver settings.

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Answer 4

Drew Reece

Level 6

10,666 points

Jan 19, 2018 10:13 AM in response to kingfisher500

You could try the caffinate command to prevent sleep if you suspect that is the reason…

http://osxdaily.com/2012/08/03/disable-sleep-mac-caffeinate-command/

There are also third party apps that will keep a Mac awake search for similar terms in the App store etc.

It can be difficult to estimate the total duration for encryption when massive amounts of data are being processed - the size of files can also effect the rate (e.g. if many small files are being read & re-written in an encrypted form). Fusion drives use a slow spinning disk for most of the storage - which can explain why it takes time.

The safest option is to just leave it running.

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Answer 5

Jan 20, 2018 8:46 AM in response to Drew Reece

I looked into caffeinate. I downloaded AntiSleep from the App Store. That did not seem to make any difference.

But, I guess that it just takes a long time for the 2 TB that I have on the disk. 96% percent complete, last night. 99% complete, a few minutes ago. Finished now (11:45 AM).

I wonder how long it is going to take to encrypt my Time Machine backup.

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Answer 6

Drew Reece

Level 6

10,666 points

Jan 20, 2018 10:26 AM in response to kingfisher500

kingfisher500 wrote:

I wonder how long it is going to take to encrypt my Time Machine backup.

Probably ages.

Time Machine is a complex user of advanced file system features. It will have a backup of everything the internal disk has & multiple versions of many files too.

I'd suggest you get your system in order before you begin, e.g. perform any updates to the OS, apps & reboot so that the task can be left alone. It should run in the background but I have seen complaints that it appears to stop (hence my caffeinate suggestion).

Also bear in mind that TM disks are generally external drives, so network or USB speeds can slow performance. Connect it directly to the Mac via the fastest interface you can use.

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Answer 7

Jan 21, 2018 7:29 AM in response to Drew Reece

Everything is now proceeding well on the Time Machine (physically connected external drive) backup encryption.

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Answer 8

The-11

Level 1

8 points

Feb 18, 2018 5:23 PM in response to kingfisher500

I have a 500gig SSD and it has taken 7 days to complete. If I would of know this I would of never turned it on.

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Answer 9

Mar 10, 2018 11:30 AM in response to The-11

and on the 7th day, God rested.

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