Anyone with CCC slow BU Issues?

I’m beginning to wonder there is some way to improve the performance of Carbon Copy Cloner on my monthly bootable backups that I swap offsite. Because of the swapping the device is usually 2 months of changes when I get it back for an update. I’ve had the most recent update running on my iMac now for 15 hours and it’s less than 3/4 of the way done.

I already do a daily BU to a separate hard drive.

This is my offsite BU and as such doesn’t get updated that often, I have 2 drives and swap with another person in a town about 75 miles away from our location.

I already know that over the 2 months between any specific drive getting used for this critical BU I will have probably touched or modified thousands of files but when I can’t use my main machine for over a full day it’s an issue even if it is only once a month.

Any suggestions of where to start looking to improve this performance bottleneck?

Did you make sure that macOS is prevented from making a Spotlight index for the external drive (System Preferences>Spotlight>Privacy)?

Did you create a support ticket at Bombich?

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Bombich support is very skilled and he responds quickly.

How much are you backing up in this 15 hours? I do mine weekly and it usually takes 1-2 hours.

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I had done that a long time ago but somehow those settings got reset because the system was trying to do a spotlight index of everything. I’ll fix that and see what happens. If still a problem I’ll talk to support .

I’m at 16 hours now and still have more to go. About 2 TB total.

Reach out to support. Unless you change a ton of files. Double check you have incremental backup checked.

It may be that the target drive is starting to fail.

Yup. I was going to suggest running Disk Utility on it, and Disk Warrior, if you have it.


I do mine weekly with CCC and it usually takes 15-25 minutes.

Glad I asked. :wink:

If you still have a problem after properly configuring your system this is an issue you really need to address with the dev.

I clone weekly to a Samsung SSD – about 600 GB total clone-size. Takes about 15 minutes.

Yes on verify (been through a BU that wasn’t verified disaster so verify is my belt and suspenders plan) I had been wanting to keep the history, i have gone back as much as 4 months to recover files in the past. I’ll have to think abit more on that though.

OK Don’t have Disk Warrior but did run Disk Utility and no problems found. We’re also talking about 2 different actual drives.

I have noticed this exact issue over the last few of months. I had a 32 GB backup that took over 4 hours. That was the worst one I complained about with Bombich Software. They seemed to think it was nothing unusual, but I disagree compared to my experiences using CCC over the years.

My data set backup is 9+TB, with 100-200GB of changes per back up … 20-25 min over USB 3.1 gen 2.

This support thread (from awhile back) points to an anti-virus interfering with the copy times:

I upgraded to CCC and hope to see some improvements.

OK no antivirus SW running here

System is an iMac 2013 with USB 3
I run 2 backup tasks First one is my main hard drive
1 TB source
51GB copied
17:21 hours
Second one is a NAS partition
1TB source
2GB copied
4:23 hours

A previous run of the same tasks
1 TB source
83 GB copied
14 hours

1 TB source
123 GB copied
4 hours

So the results are really odd

And all the drives are prevented from making a Spotlight index?

Generally, long backup times for the first backup usually are pretty long for big drives, be it in CCC or SuperDuper!, but the incremental backups are usually much quicker…

Any luck contacting support of CCC @OogieM?

I decided to wait until I have a bit more data after verifying configurations. Then I got sick and haven’t done much. Hpe to get back debugging this next month.

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