APFS, Time Machine and Big Sur

[cmaier]

I do like the historical look back of Time Machine, though. I use CCC when I need to make a dedicated copy-- I've got a 2013 MP that needs service, so I'll CCC the internal storage to that T7 drive, wipe the drive when I bring the MP in for service, and then restore the CCC copy.

I haven't gone through the hassle of dealing with Synology on this issue, but I suspect the problem is that a TM backup is a huge number of little files which is not well suited to the type of asymmetric array Synology uses. No RAID likes lots of little files, but I have an array of 4 identical disks in my OWC box and it's probably easier to handle with simple striping than it is with whatever games you need to play to spread access, parity and redundancy across drives of different sizes and speeds.

Yeah, i use time machine (rotating between both syn boxes) for redundancy, and then use CCC once every two weeks to back up onto a wired drive. Belt and suspenders. I’ve never had to resort to the CCC backup. The speed of the time machine backups doesn’t trouble me to much because it gets in a few backups a day on each box. Whenever time machine does determine That the archive is no good (which it does every 4 or 5 months) on one of the boxes, then I just suck it up and take the 2 days it takes for a full backup. Since it’s normally incremental, it’s not too bad (way slower than it needs to be, but it doesn’t bother me as long as i always have a recent backup in a couple of places.). I actually back up from 5 different macs onto the two synology’s (hint: set up backup accounts on the box and set quotas!), so that probably doesn’t help my performance

 

[Analog Kid]

Yeah, i use time machine (rotating between both syn boxes) for redundancy, and then use CCC once every two weeks to back up onto a wired drive. Belt and suspenders. I’ve never had to resort to the CCC backup. The speed of the time machine backups doesn’t trouble me to much because it gets in a few backups a day on each box. Whenever time machine does determine That the archive is no good (which it does every 4 or 5 months) on one of the boxes, then I just suck it up and take the 2 days it takes for a full backup. Since it’s normally incremental, it’s not too bad (way slower than it needs to be, but it doesn’t bother me as long as i always have a recent backup in a couple of places.). I actually back up from 5 different macs onto the two synology’s (hint: set up backup accounts on the box and set quotas!), so that probably doesn’t help my performance

Yeah, sounds like we've got similar setups and similar problems. Multiple Macs, each with a local direct attached backup and each with their own login credentials backing up to shared NAS. The smaller macs back up to the same NAS without much headache. The Mac with all the external drives attached takes forever, occasionally corrupts, and then needs to start from square 1 (though for me, that first full backup seems to take about 4 days). Glad to know I'm not the only one seeing this.

 

[HDFan]

At one point i had a synology engineer remote into my box looking into why it was so unreliable and slow with backups, and he

I suspect the problem is that a TM backup is a huge number of little files which is not well suited to the type of asymmetric array Synology uses.

I have and continue to have transfer issues with both QNAP and Synology NAS units.

1. With a 10 GbE Mac I was seeing glacially slow network transfer rates when doing CCC backups, in the 25 Mbps range. A thunderbolt 3 copy on the QNAP did not show the problem. Turns out it was an issue with my 10 GbE switch. The one I had didn't play well with my Mac. Switched to a Netgreat switch and the problem went away.

2. TM backups on both are still glacially slow, even for incrementals. At least 2 - 4 hours or even more.

 

[gilby101]

There doesn’t seem to be any real advantage to using APFS for a time machine drive, so I’d just ignore that it’s coming.

Try it. I am using an APFS partition (on a USB HDD) for Time Machine. It is ever so much faster than to an HFS+ partition. Presumably due to the use of snapshots and (maybe) block level updates.

I just hope Apple decide it is reliable enough to include in the final release.

 

[bad_friday]

Unfortunately the TM-Backup made within Big Sur isn't recognized with the recovery feature (booted with lt alt and r).