Last Week on my Mac: The strangeness of Time Machine, and App Store conflict

It’s a long time since my Mac last behaved in the weird and idiosyncratic ways that it has since I upgraded to Sierra. The first oddity was to become so overwhelmed trying to run the processes that were active, that it stopped its clock, and all user control, for periods of a minute at a time. I have been kinder to it since, and the clock now ticks away quite regularly.

The other seriously spooky behaviour I still cannot explain.

For very many years, I have left my main working Mac running all the time. Sometimes, as a special concession, it gets shut down over Christmas, and when we go away. Although I have been happy to lets its display and CPU sleep, my current iMac has been unable to sleep the system without sleeping its hard drive (part of a Fusion Drive), so I cannot let the system go to sleep. Accordingly, since I commissioned this iMac last December, it has run Time Machine backups every hour, night and day – until I installed Sierra on 20 September.

Since then, backups have occurred less regularly. When I get up in the morning, it is now usual for there to have been no backups during my sleeping hours, and when I first tickle the trackpad, that triggers the first backup of the day.

It is no longer easy to see when backups have taken place, but when I worked out how to do that in Terminal, I discovered that the time intervals between Time Machine’s backups were anything but the advertised hour (as it always had been). A simple plot in Numbers of the periods since the last backup, according to the time of each backup, showed huge variation in the interval: from 45 minutes to over 6 hours.


Then, most recently, those ‘smart’ backups vanished, and my iMac reverted to making regular hourly backups, 24 hours a day.

The only significant difference now is that my Magic Trackpad 2 is left permanently tethered by its USB charging cable, until I can sort its Bluetooth problem out or exchange it for one which works wirelessly again. I cannot for the life of me understand how that might affect Time Machine, but it is the only significant change which has taken place since I experienced irregular backup intervals.

I will continue to keep an eye on this, and hope soon to be able to explain what has been going on. Maybe there is a ghost in this machine after all.

The App Store

Apple is providing both carrots and sticks to us, as users, and to all developers to make its App Store the major, if not only, means for distributing software for macOS. Under the Store’s current rules, though, certain classes of software simply cannot be distributed through the Store: for example, apps which do a lot outside their security ‘sandbox’.

Apple has not faced up to the fact that many Mac users have to use products which cannot fit its current model, even though its own products, like Xcode, can employ various cheats which work around its own rules.

For most products, I am fairly happy with the App Store, and the restrictions which it places on the apps which it sells. But every now and again, Apple can’t cope with the conflicts of interest which it has inflicted on itself.

A case in point is the invaluable app Dash, from If you do any sort of development, from crafting shell scripts to writing HTML or LaTeX, Dash is an essential tool, as it enables you to browse and search a vast range of documentation, including Apple’s extensive documentation sets supplied with Xcode.

For some reason, Dash’s developer has had a falling out with the App Store, resulting in Dash being dropped completely from both Apple’s macOS and iOS App Stores. I won’t go into those reasons here, as I am still not sure that they are particularly clear, and they are not actually relevant to my concerns.

So on the one hand, Apple is telling us all to buy our apps from its Stores, and ensuring that they are the best-secured way to obtain and update software on our Macs and iOS devices. On the other hand, Apple pulls a product which we have paid for, for which I am not aware that there is any substitute offered in the App Stores, and whose developer was very happy to continue to sell through the stores.

If the products were malicious, flawed, broken, or otherwise bad news to the user, I can see the sense in Apple’s unilateral if not arbitrary decision. But I do not know of a single Dash user who wants its products dropped from sale in the stores. As Apple has a complete monopoly over iOS app sales, and is trying to tell us that it should have a near-monopoly over macOS app sales, dropping important, well-used, and well-liked products harms its developers and users.

If Apple wants most apps for macOS to be sold through its App Store, it is going to have to behave less tyrannically, and negotiate with developers rather than throw them out of its crib whenever it wishes.

Perhaps all it needs is a bit of competition.