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

[Robert Lane]

Yes, High-Sierra has been out for a while now and most consider it stable. However its really not nor is it as fully developed as Sierra and here's a few nearly non-documented reasons *not* to update to High Sierra - yet.

First and most critical:
There's a "data-growing" bug that has been reported to Apple but not yet been addressed or a fix issued. The issue is that High Sierra slowly and sneakily keeps growing in size in the background, eventually taking up all free space on the installed drive. The common response from Apple so far has been to, "...backup all your data and reinstall the OS using the App Store installer...". That "fix" doesn't work as the OS will eventually start it's sneaky background build-up all over again.

Second:
You can't fix the directory. The guys at Alsoft, makers of DiskWarrior have been working for over a year to come up with a version that will successfully talk to the new APFS volume structure and can't. Apple has yet to release the critical structure information required to make this happen and, according my sources the actual data--code design of High Sierra is actually a moving target.

Unlike every other previously released version of OSX, High-Sierra's core code is not locked and is changing with updates. The most recent change, 10.13.3 actually completely re-wrote some core code which changed the foundation of High Sierra. Not something published nor evident to the end user, but a perfect example of why Alsoft hasn't been able to release DiskWarrior to fix directories on APFS. So that means if something goes horribly wrong with your High Sierra directory the only option you have to do a re-install of the OS. Not exactly a good solution.

(Note: DiskWarrior and be installed and run on High Sierra but it can only fix HFS+ volume directories)

Three:
For those of us who are using external HDD RAID arrays the APFS volume structure both *not* an improvement in data-handling but the reverse, it's worse! There's a lot of documentation about the file-handling difference between APFS and HFS+ volumes, APFS was designed to optimize how SSD's work. That schema actually puts greater headroom loading on HDD-based systems making data-block allocation harder for spinning-disks.

My gut tells me it's this new type of structure that's causing issue 1 above, because the OS is constantly taking snapshots of itself to use as quick-reference points that help in "instant" data access rather than the seek-and-find method HFS+ uses. Makes sense; if every block gets a snapshot then the data-directory is constantly growing, right!

Bottom line: If you're on a Sierra-based system, stay there. I won't go to High Sierra again until Alsoft is able to fix the directory!!

[If you have a system that shipped with High Sierra you're stuck. The mainboard firmware won't allow a retro-grade to a previous OS. If you've upgraded to HS and want to go back, you can. Depending on your situation it might be a hassle, but check the dozens of articles online about the options.]

[Pete Cofrancesco]

Good to know.

I recently upgraded from Yosemite to Sierra on my 2009 Mac Pro. For a long time I wanted to update my OS so I could get the latest FCPX but the App store wouldn’t allow me to update past Yosemite. I recently stumbled on a web site that had a special utility to get around it. Downloaded Sierra on a newer mac and when I ran the utility it said nothing needed to be changed and low and behold Sierra installed and has been running without issue.

[Pete Bauer]

My advice: heed Robert's advice.

I waited and watched until the current MacOS High Sierra 10.13.4 was out before upgrading from Sierra...it seemed that finally online problem complaints had died down. Maybe not so much; I definitely feel now I jumped the gun.

The 1TB SSD on my mid-2014 15" MBP has the fill-up problem, which I unfortunately hadn't been aware of. Discovered this while trying to edit DV Info Net NAB videos earlier this week. Fun. System sitting at 474GB now...that's a LOT of system, eh?

To be as polite to Apple as I can manage presently: MOST unsatisfactory that this kind of major bug was released at all, much less still not fixed or officially worked around.

[Robert Lane]

Pete,

Get back to Sierra, immediately. With that much OS inflation your Mac will become unusable fast.

There is more than one-way to retrograde, even if you don't have a cloned backup of your OS and apps. I had to do that very method but it worked and I'm back to Sierra and things are grand.

If you don't find a solution that works for you PM me and I'll walk you through the process - but don't delay.

[Pete Cofrancesco]

I am on Sierra don’t plan on getting High Sierra now that I read this besides I cloned my Yosemite before upgrading. I’m not sure if they blocked the update for a good reason other than to “encourage” you to buy a new computer or Apple just not caring.

[Tim Lewis]

And there are monsters under your bed!!!

Scaremongering. I use High Sierra on three Macs without issue.

AFPS does NOT affect HDDs. It is only SSDs that get AFPS installed on them with the High Sierra upgrade. My 2011 MacBook Air is the only SSD Mac I have. High Sierra did NOT change the file structure however, possibly because of its age or because it was formatted FAT32 so I can run Boot Camp on it.

My 2011 iMac i5 1TB HDD shows no sign of this either. My 2017 iMac i7 1TB Fusion Drive shows no sign of this. These are both NOT AFPS formatted.

I think the issue may not be as widespread as the OP has thought it to be, but if you are running a relatively new MacBook, it is probably something of which you should be aware.

[Robert Lane]

Tim,

1. There IS a detriment to APFS formatted volumes that live on HDD's. Many have incorrectly assumed that if the boot drive was auto-formatted APFS (because it's an SSD) that all other volumes need to be as well.

2. The other related issues are in point of fact all about the APFS format. High Sierra does run (mostly fine) on an HFS+ volume and does not grow in size because it's *not* APFS.

Apple has quietly admitted - and only to it's third party vendors, that APFS is "...under continual development...". Which as it has been described to me by insiders is a safe way of saying, "...we know there are issues, we're working on it."

If it's fear-mongering then it's as real as it gets with companies like Alsoft, who are continuing the struggle to provide a stable, usable APFS file-system management product. Others in the data-management game are also grinding their teeth, waiting for Apple to finally supply the code they need to finish their HS-compatible products.

[Boyd Ostroff]

Thanks Robert, I had no intention of upgrading anyway. I am very reluctant to upgrade MacOS, my two main systems were on 10.8.5 until about 6 months ago when I upgraded to Sierra. I have so much legacy software that would be too expensive to upgrade so I subscribe to the "if it ain't broke don't fix it" philosophy. :)

[Chris Hurd]

I'm standing firm on Sierra 10.12.6.

[David Knaggs]

I run 2 iMacs (at different locations). Soon after High Sierra first came out, I upgraded one of them and left the other on Sierra. I noticed a problem (difference) with the High Sierra iMac almost immediately.

Specifically, I had several hundred still images I'd taken which were on a portable hard drive. On High Sierra, I tried to quickly scroll through all of the photos (using the space bar - if you use the Mac OS, you'll know what I'm talking about) and found that it was taking maybe 5 seconds before an image could be viewed using the space bar. Before High Sierra, it was always instantaneous. Multiply 5 seconds by several hundred photos and it was an excruciating time-waster. I think that this phenomenon might have been due to some of the things which Robert was talking about in his post.

Later, I took that portable drive to the iMac with Sierra and found that it showed each photo instantly. So I knew then that it wasn't a problem with the drive. It looks like High Sierra caused the problem. To be fair, Apple have issued a couple of High Sierra patches since then and that problem appears to have been solved. But that experience left me with a distrust of High Sierra, so I left that other iMac on Sierra. Until about a week ago, when Apple issued new upgrades to FCP X and Motion.

For the first time, these upgrades are incompatible with Sierra and can only be accessed by upgrading to High Sierra. Apple have made some excellent upgrades (in my opinion) to FCP X in recent times so I weighed the possible benefits against the risks and I upgraded the other iMac to High Sierra. And then Robert started this thread a day or two later. Oh, well. It's still more important to me to keep FCP X current. But that's just me. By the way, the High Sierra upgrade also knocked out my old copy of FCP 6, making it incompatible. Not that I'd used it for years anyway (it was just a bit of nostalgia).

[Gary Huff]

I am running all of my Macs on High Sierra.

Originally Posted by Robert Lane

First and most critical: There's a "data-growing" bug that has been reported to Apple but not yet been addressed or a fix issued.

I'm not sure what this is. I have never heard of it, I have not had any of my installations of High Sierra take additional space after installation.

You can't fix the directory. The guys at Alsoft, makers of DiskWarrior have been working for over a year to come up with a version that will successfully talk to the new APFS volume structure and can't.

DiskWarrior is a great utility, one that I use myself. This only should apply to your internal SSD drive, so not having DiskWarrior compatibility with APFS volumes should not be a big deal. Your backup strategy should not involve critical files on the internal SSD. If so, you are doing it very wrong. You should not format any other drive besides your internal SSD as APFS. If you do that, you are also doing it very wrong. It should be that DiskWarrior won't fix your root, but it will fix everything else. I primarily use it to redo the directory structure for efficiency on some HFS RAID units I have. That works perfectly fine in High Sierra

For those of us who are using external HDD RAID arrays the APFS volume structure both *not* an improvement in data-handling but the reverse, it's worse!

This is very wrong. You had to intentionally go in and format these RAID arrays to APFS, OSX does not do this automatically. This was a huge mistake and you should immediately backup all the data off of your RAID (using CCC ideally), and reformat it to HFS. Immediately.

Seems to me the issues mentioned here with High Sierra stem from PEBCAK.

[Ricky Sharp]

Originally Posted by Robert Lane

There's a "data-growing" bug that has been reported to Apple but not yet been addressed or a fix issued. The issue is that High Sierra slowly and sneakily keeps growing in size in the background, eventually taking up all free space on the installed drive. The common response from Apple so far has been to, "...backup all your data and reinstall the OS using the App Store installer...". That "fix" doesn't work as the OS will eventually start it's sneaky background build-up all over again.

If you bring up the info on your boot drive, what does it show for Available space? Do you see a figure listed in parenthesis marked purgeable? APFS storage on my boot drive (High Sierra) does change over time, but space is ultimately re-collected. Especially if you need to reboot.

For example, I installed a 36 GB application around lunch one day. I started with 500 GB free then went down to 460 GB or so. Made sense. Later that same day, an update was available. So re-installed 36 GB over the existing application install. Available space dropped down around 425 GB. I did need to reboot later, and the available space went back around 460 GB.

Having said that, outside of email, OS caches, system preferences, etc, the boot drive remains fairly static in terms of storage. Largest changes involve applications that are quite sizable. So I've never seen the drive fill up.

Are you perhaps using the main boot drive for data storage too? In my case, all data are to external RAIDs. One main RAID 10 for primary data. A RAID 0 for a scratch disk. And a RAID 1 for backups.

Perhaps there are some tweaks that can be done to the OS to more aggressively re-capture purgeable space if indeed that is the issue you're seeing.

[Paul R Johnson]

I had to buy a new MacBook before Christmas - it has High Sierra on it and I'm not seeing any snags apart from one app no longer able to be run, when brought back in from the backup, or installed fresh. other than that I've discovered no issues I can point a finger at?

[Boyd Ostroff]

Originally Posted by Gary Huff

I'm not sure what this is. I have never heard of it, I have not had any of my installations of High Sierra take additional space after installation.

Could this be it? https://discussions.apple.com/message/32740453

[Gary Huff]

Originally Posted by Boyd Ostroff

Could this be it? https://discussions.apple.com/message/32740453

You mean the Time Machine backups? I don't use Time Machine, so it could be that.