Home Forums Peripherals & Multimedia Peripherals Time Machine Empty

Here is a real head spinner. TM ( dedicated external hard drive), normal for months, lots of entries, today totally empty.. wtf? I look at settings is says been copying. ANy ideas?

https://imgur.com/a/ueHfaSb

Other external Hard drives look fine.

Nevermind, DU shows 8 tb drive, 50 free, now clicking there things coming up, but still why ever should you click and see 0?

It is all in the timing of when you looked. Time Machine was in the process of backing up 282.95+ GB of data to a volume that only had 50.22 GB of free space. In order to do that, Time Machine must Prune the existing data set which involves deleting older files that have not been recently accessed and rebuilding the data set. A long processor intensive task.) For safety, the new Time Machine backup is first copied to the drive and only when that is complete is it added to the Time Machine data set so at least twice as much fee space will be needed temporarily.

Your second check was taken after the process had time to complete.

What is the the capacity of macOS HD? What is the capacity of your Time Machine drive (NOTE: that is capacity not free space)

Thanks Joe, great info.

TM is 8 TB

Mac is 1 TB.

I never seen that happen, so now I know.. If I could clone you, I'd have you here as a calming influence!

At first, I ASSUMED your Time Machine drive was under-sized, but that assumption was false. You have simply filled it to capacity. The good thing is Time Machine can continue to operate by "pruning" the data set. The downside is it is taking an hour or more to do the pruning, which means it may be time to start the next backup before the last backup has completed. This undoubtably would have a noticeable negative impact on system performance.

Ask yourself, how often do you recover files from Time Machine, and how far back in time you have gone to get the data you wanted. With that in mind, consider erasing your Time Machine drive and starting over from the current time. This is not an essential step, but worth thinking about.

The solution to that is to not have TM run every hour. Who really needs that on a home computer? Even my work computers were never backed up that often.

kevs is a photographer, and this is his business (as well as home) computer, so it's probably wise of him to back up frequently as he works.

During the hour+ that the backup is going on, it is eating lots of CPU cycles and having a noticeable negative impact on productivity.

Thanks I'm not even cognizant of the every hour frequency -- was not even aware. I'd be ok with much less. frequency.

Ok found the preference... could do every day. But why think the minute I do that I'll have 5 new instance of needed some work done 3 hours ago!

In reality only dip into TM every 6 months for something created a long time ago.

So, the entire system, I'd get much less Beachballs?, which I see all the time beachballs, would be much less going once a day, vs, once hour?

You think that because you have learned Murphy's Law is not a myth. Time Machine is a tool that we seldom use, but when we do, it can be a lifesaver.

Unless Murphy's Law kicks in. (I find most of my TM recoveries are either within the last few hours, or some months back.)

I find hourly backups to be small enough to be unnoticeable, daily backups, and monthly backups involve concatenating backup datasets and require significantly more resources. Throw in the necessity of pruning the dataset to make room and even hourly backups can require significant CPU and I/O resources resulting in sluggish disk I/O, and momentary system freezes, beachballs not so much. Beachballs they are more typical of network slowdowns.

To be honest, I don't know what to recommend. There are too many variables with too many unknowns. I don't think you will gain much, if any, in the long run by going to daily backups instead of hourly backups, and you would lose the short term Murphy's Law safety net. The only way I can come up with to save your existing backup and continue to grow it is moving it to an LTO tape drive, but those are Pricey with a capital dollar sign.

Joe, great answer: Murphy Law! I'll keep it as is.

Two years from now, Murphy will speak right after editing a photo for 45 min! Or something like that ...