After APFS conversion SD Smart Update is super slow

[mattone]

Happy New Year!

I'm seeing a very slow Smart Update from my 13" 2017 MacBook (no-touchbar) after updating to High Sierra and having macOS convert my internal SSD to APFS. Currently the effective copy speed is 0.68 MB/s. Would this be attributed to all the new data (from the upgrade to High Sierra) or due to updating from an APFS volume (internal SSD) to a HFS+ volume (external spinning HD)?

My Super Duper back is a 500GB partition on a 1TB spinning HD connected via USB 3.0 thru the Thunderbolt Display's usb ports. Normally I see much faster throughput so I'm surprised by this.

Thank you.
Matt

[dnanian]

That seems awfully slow, yes. This is your first copy? It's probably because of the hub/etc. What happens if you connect it directly? Did you do an erase or a smart update?

[mattone]

Originally Posted by dnanian

That seems awfully slow, yes. This is your first copy? It's probably because of the hub/etc. What happens if you connect it directly? Did you do an erase or a smart update?

This is my first copy since the upgrade. I would connect directly but I don't yet have a USB-C > USB-A cable. However I've been using the Thunderbolt Display's hub for a long time w/ much better throughput than today's. This backup is a Smart Update.

[dnanian]

It may be that it needs to delete a lot of data, or that the drive is highly fragmented and lots of files are being replaced.

I'd use Disk Utility to erase it. Then, add it to the spotlight preference pane's "Privacy" tab. Then Smart Update the empty drive.

[mattone]

Ok. Sounds like a plan. I'll report after it completes.

Thanks,
Matt

[mattone]

Would you recommend reformatting the HFS+ volume (external drive - spinning) to APFS? I' only use this volume for my Super Duper clones.

[dnanian]

Yes (see http://www.shirt-pocket.com/blog), but recognize that APFS is about 20% slower than HFS+. Other advantages outweighs the speed issues, and no doubt Apple will improve that over time.

[mattone]

I formatted that partition as APFS after cancelling the backup. Its now running at ~7MB/s. Seems slow to me still but just to eliminate the possibility off the Thunderbolt display being the source of the bottleneck, I'll spring for a USB-C cable and run it again.

Thanks,
Matt

[dnanian]

Remember: lots of small files are slower than large files... speeds will vary along the way.