Mac Sierra Users: Don't Upgrade to High-Sierra - yet

[Pete Cofrancesco]

I’ve never used Time Machine. Like most of Apple software it’s not transparent what it’s doing underneath its simple veneer. I wanted to take a snap shot of my OS before doing an update but it said it needed a hard drive larger than 5tb to backup to despite that my os was less than 100gb. I’m guessing it was trying to backup all my archived projects on my secondary drive. I couldn’t figure out how exclude my archive so I ended up using a cloning software instead. I’ve read many complaints about it slowing things down running backup tasks in the background.

[Robert Lane]

The OS-growing issue has nothing to do with Time Machine. (I only use Carbon Copy Cloner for all my clone/backups. Been rock-stable issue-free for years.)

Although Apple has admitted the issue only to third-party developers they haven't confirmed the cause. My gut and years of diagnosing OS-related issues is that it has everything to do with the fact that High-Sierra is constantly making "snapshots" of itself and, copies of changed data. Here's an interesting article recycled many times on the 'net:

https://www.makeuseof.com/tag/new-ma...ow-apfs-works/

Here's excerts from the article that point to what is most likely the underlying cause:

"When you copy a file, APFS creates a new entry in the file system that points to the same bits as the original file. This is not a shortcut — to the Operating System and Applications, they are separate files."

"APFS handles changes differently. Each change you make to a file saves in a separate location from the original file. This process is a native way to support versioning as well. It also means that your original file is still only the single original bits. So is the copy that you made. On your day to day drive, this may not save much space. That may be different if you have files that change frequently."

From all that I've read and the whitepapers shared with me from these third-party developers, Apple seems to have forgotten how to tell the OS to get rid of the obsolete copies/snapshots over time, instead allowing a massive yet not-user-accessible library of hidden reference files that keeps growing on itself. Like a central cache file gone beserk.

The whole point of this snapshot-happy OS as Apple's own marketing indicates, was to make file copying/changes near instant and to supposedly speed up file transfers etc. (Albeit only on SSD installations.) I see the logic behind the design, they just forgot to write code for managing all these hidden copies.

As has been told to me more than once, Apple's core HS code is a constant moving target; they are working on refining this new APFS structure. The ".3" update which was massive and took a very long time to apply, is witness to this "we're working on it..." note given to the developers as to why they haven't been able to consider core code "gold" yet.

Eventually it will all get sorted out - it has to, otherwise the OS will keep eating itself to the point of "data extinction", where there's no free space left on the installed drive. But for now my advice remains: Get back to Sierra asap and, if you haven't made the "upgrade", don't.

To wit, there is no must-have about HS that makes it mission-critical to do work. Although there are some "new" features on certain Apple-branded applications that are only operable in a HS environment, don't be fooled into thinking you're behind the times working on Sierra. I know of several post/edit houses that are still on El Capitan and are doing just fine.

[Gary Huff]

Originally Posted by Robert Lane

But for now my advice remains: Get back to Sierra asap and, if you haven't made the "upgrade", don't.

My High Sierra install is running just fine with no issues, so for myself and those like me, why get back to Sierra ASAP?

[Jonathan Levin]

I've had High Sierra running on my mid 2010 Mac Pro for months with no problems, except my machine is a bit long in the tooth.

As mentioned above, maybe this is just related to SSD drives. I hope they get that taken care of. At some point in the next 6-12 months I'll be switching from a desktop to laptop,

[Jeff Donald]

I don't post here as much as I'd like to (or used to), but I do have considerable experience with Apple computers since the early '90's and I am a former Apple employee. I'm also the former Moderator of the Apple forum here on DVInfo, back when Chris had moderators for each of the forums.

I've been using High Sierra since it came out, on multiple machines (iMacs and MacBook Pro's) and like the posters above me, I am not experiencing any the issues referenced by the OP. I would suggest doing what I do when a new OS comes out and that is to create a seperate partition on your disk for the new OS. Finish all open projects before doing any upgrades and make backups of original files etc. Don't rush into upgrades blindly, but also don't NOT upgrade blindly.

I also find several comments difficult to fathom. High Sierra will not automatically convert a HDD or external SSD's to APFS from HFS+ without really jumping through hoops. If you own a RAID, consult with the manufacture of the RAID before upgrading. Most of the major RAID companies issued cautionary updates advising customers not to force the upgrade of their RAIDs to APFS. These advisories should not be ignored.

Your mileage may vary and I don't mean to sound like I'm lecturing, but I find a lot of information in this thread misleading or not based in factual evidence.

[Ricky Sharp]

Originally Posted by Jeff Donald

I also find several comments difficult to fathom. High Sierra will not automatically convert a HDD or external SSD's to APFS from HFS+ without really jumping through hoops. If you own a RAID, consult with the manufacture of the RAID before upgrading. Most of the major RAID companies issued cautionary updates advising customers not to force the upgrade of their RAIDs to APFS. These advisories should not be ignored.

This is correct. I'm primarily a software developer and thus have read the various developer notes too about each OS release. Conversion to APFS is not automatic. And, as an owner of three external RAIDs, I kept all of them on HFS+.

I still contend that those with the issue may have lots of data being written to the main boot drive. Best to double-check just what applications may be doing that. In my case, virtually all data is on external RAIDs. The largest storage size changes to the boot drive come with installation of software. The boot drive of course still has a ton of writes going on, but mostly very small (e.g. incoming emails, preference file changes. Basically any change primarily to ~/Library/

[Paul R Johnson]

Ironically - yesterday my MacBook did an update. It often does these, but this was a big one, and now it reports my Microsoft Office is now in need of updating. Grrrrrr.

[Robert Lane]

Here's proof in the pudding that in point of fact, High Sierra does "grow" in the background with all the snapshots it takes of itself, rendering huge free-space unusable:

https://forums.macrumors.com/threads...ystem.2073174/

The guys at Daisy Disk have noticed this same issue and created a built-in utility to reclaim all that space:

https://daisydiskapp.com/manual/4/en...temTooBig.html

In short, it's not a bug instead, HS is allowed to take up to 80% of the usable space on the SSD it's installed on with all the snapshots it creates. (Note: These are NOT Time Machine backups).

Most people don't know this is happening because on an SSD technically there wouldn't be a performance degradation or at least one that shouldn't be noticeable in normal use. But if you're tasked with high-end 4K video editing and, depending on your physical setup this could in fact be a deal-killer issue when it comes to free space.

If you're knowledgeable with TERMINAL commands you could use the one mentioned in the macrumors forum to delete these files. Or for $10US you can use Daisy Disk's utility method.

I have no idea if Mojave is going to follow this same schema, but considering the guys at Alsoft still haven't been able to create code to run DiskWarrior on HS things look foggy for OSX future code.

[Robert Lane]

And...

The guys at Bombich (Carbon Copy Cloner) have also utilized a method for recovering freespace due to snapshot storage. There's also a method for managing the retention policy - how often OSX creates a snapshot. Could be someone might create TERMINAL code for stopping snapshots altogether someday!

https://bombich.com/kb/ccc5/leveragi...n-apfs-volumes

[Boyd Ostroff]

Robert, isn't this a feature of APFS as opposed of High Sierra? I'm sticking with Sierra, but was under the impression that installation of APFS was optional in High Sierra.

Was just reading a thread at MacRumors where someone installed the Mojave beta on the stock 5400RPM hard drive in a 2014 Mac Mini and is getting 35MB/sec read and 7MB/sec write speeds! I have one of these machines and it clocks at about 100MB/sec read and write with Sierra. I know beta software is not optimized, and these are slow disks... but that's crazy!

[Gary Huff]

Originally Posted by Boyd Ostroff

I'm sticking with Sierra, but was under the impression that installation of APFS was optional in High Sierra.

It's not really optional. It won't convert spinning drives to APFS, but if you have an SSD, you really have to finagle your way around the High Sierra installer in order to get it not to do that. I did it with my iMac, but it's not the easiest workaround.

[Robert Lane]

To be clear:

When installing High Sierra on an internal SSD the installer will ONLY allow for an APFS format. Only during the Beta did you have an option for HFS+ or AFPS.

High Sierra *only* creates these annoying background snapshots on an APFS formatted SSD. So if for example you have a spinning-disk HDD that you've installed HS on, then it won't be APFS and those automated snapshots are NOT created.

So far there are manual TERMINAL commands that can delete the snapshots and recover the lost free space or, as I mentioned both Daisy Disk and CCC have built-in utilities to do the same.

(NOTE: CCC's version seems to be dealing with only the "snapshots" that CCC creates during backups. I know, now we're talking about 2 different kinds of snapshots now - the ones created by OSX and what CCC creates. Keep that in mind and READ the documentation from CCC.)

Microsoft tried this same schema years ago with so-called internal backups just after Win98 and it was a disaster too. And then Apple not to long ago introduced "versions" in OSX with regards to saving multiple versions of the same document and other files - just in case you wanted to go backwards. Now this automated "saved last state" for the OS is just... arghhh. The code-monkeys at Apple have gone overboard with trying to make OSX fool-proof for the non-power user.

(It sure would be nice if there was a "pro" version of OSX without all the necessary bells and whistles like all the "i" apps, screen animations/fades etc and just concentrate on getting work done. Hmmm, MS has different versions of Windows - why not?)

The non-pro/power user of OSX won't know or care about the free space being chewed up, but my advice is that if you're using High Sierra then keep tabs on future posts about code to *disable* snapshots altogether and, in the meantime use Daisy Disk to clean up your SSD from time to time. Most especially if you need to install new software or, make a new partition for Boot Camp for example.

[Ronald Jackson]

So I'm about to get a new iMac which will arrive with High-Sierra installed. It will have a 2TB "Fusion Drive".

My current old iMac is on "El Capitan". I use it for FCPX with projects on a number of "conventional" external drives. I will be using the same drives with the new Mac for new FCPX projects.

Do I need to worry about the issues (mainly above my head) which raised here?

Ron

[Boyd Ostroff]

I don’t think you need to worry about any APFS issues on that new machine. Unless I’ve missed something, APFS doesn’t support Fusion drives yet, although Apple has said that it will in the future. So I think your internal drive will be formatted as HFS, which has been the Apple standard for many years. Now there may be other issues with High Sierra that aren’t related to APFS... I decided to skip it and have kept my machines on Sierra.

Just curious... did you have an urgent need to get this new machine? There are lots of rumors that Apple will release a whole bunch of new computers in September or October, including a new iMac with improved graphics.... https://www.macrumors.com/2018/07/11...ates-fall-kuo/

[Gary Huff]

Originally Posted by Robert Lane

When installing High Sierra on an internal SSD the installer will ONLY allow for an APFS format. Only during the Beta did you have an option for HFS+ or AFPS.

You can technically still do that now, I just did it a few months ago with a new iMac, but it involves running the High Sierra installer via Terminal commands and it's not for anyone who isn't comfortable tinkering around with Terminal.