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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

26 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

24 replies

Oct 27, 2024 3:50 PM in response to raphael38

when the stack of complaints get tall enough< apple will invest resources to investigate. be sure you have, as described above, asked Apple support to create a formal, tracked Bug report, or add you information to any existing report.

If that is too hard, then leave a complaint on the feedback page, also referenced above.

Posting here allow us to discuss it, but Apple does not follow these discussions.

Oct 28, 2024 2:30 PM in response to vojtech257

vojtech257-

Backup onto a LOCAL drive is not what others on this discussion thread are complaining about. They all have backups on a remote disk or shared disk such as a server or NAS. They are seeing a new task, diskimagesiod consuming VERY large amounts of CPU power.

if you continue to have difficulty with a Local backup, please start a new discussion.

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?

Nov 21, 2024 8:45 AM in response to liansz

It does the same thing to me. There must be a bug that was recently introduced. Because until at least 1-2 macos updates ago , there was no issue, and it has been working for about two years without any kind of issues.

Apple really needs to look into this. Not sure if its somehow related with synology nas , but I don't really think its related to synology.

update : I think its going crazy when its backing up and you connect to vpn !

The issue is it won't even stop , even if you ask it to skip this backup , until you disconnect from vpn.

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.

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