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liansz Author

Level 1

7 points

The Time Machine is causing the CPU to hit 100%.

Device Information

Macbook Pro 2020 M1

16GB + 512GB

MacOS Sequoia 15.0

Backup Device

Apple Time Capsule(A1470 2T)

The Time Machine, during the backup process, has the ‘diskimagesiod’ process consuming CPU usage that at times approaches 100%. It does not occur throughout the entire backup process; it only happens for a period of time, even if just for a few minutes. However, during these few minutes, the system becomes very sluggish. This issue was not encountered in macOS Sonoma.

MacBook Pro 13″, macOS 15.0

Posted on Sep 22, 2024 6:22 PM

Top-ranking reply

vojtech257

Level 1

20 points

Posted on Sep 24, 2024 8:05 AM

I have the same error on my MacBook Air M1.

Deleting the old backup didn't help.

Backing up to a USB drive does not cause an error.

The error only appears when backing up to a Synology NAS.

It didn't show up on older MacOS either.

View in context

23 replies

Oct 29, 2024 7:42 AM in response to vojtech257

My apologies. from your description, it sounded to me like you were making a local Backup. not to a server os shred disk.

Your suggestion about deleting old snapshots in interesting, but snapshots can be difficult to remove. ¿What method did you use to remove them? What tools did you use?

Oct 29, 2024 8:45 AM in response to Grant Bennet-Alder

As I wrote earlier, I used the OnyX utility.

I had to turn off Timemachine until I deleted the old snapshots.

Timemachine on Synology NAS is now usable again.

Although it still loads the CPU, but for a much shorter time and not at 100%.

Today I upgraded to MacOS Sequoia 15.1 I will test Timemachine to see how it works.

[Edited by Moderator]

liansz Author

Level 1

7 points

Sep 24, 2024 1:10 AM in response to liansz

Add a screenshot.

Sep 22, 2024 6:57 PM in response to liansz

That's 100 percent of ONE CPU, where you likely have 6 or more.

warpdag

Level 1

17 points

Oct 19, 2024 6:05 AM in response to ümlaut

It seems random, rebooting the mac fixes it, it is happy to backup to time machine afterwards. Clearly a bug introduced recently.

Oct 27, 2024 1:05 PM in response to warpdag

Having the same issue every now and then. force killing the process fixes the issue temporarily. you can restart the backup then.. until the process goes bonkers again. suspect a bug in there...

Oct 28, 2024 11:24 AM in response to liansz

Using the OnyX Utility, I deleted the TimeMachine APFS snapshot on the local drive.

It seems that after creating new snapshots, the CPU load has decreased significantly.

Nov 20, 2024 3:05 AM in response to vojtech257

Thanks, I had a snapshot from September, so quite old, maybe that was the one causing problems, let's see if I have the CPUs at 100% again for diskimagesiod.

The Time Machine is causing the CPU to hit 100%.