Deleting huge files, but not freeing up space!?

BigMcGuire

Contributor
Jan 10, 2012
4,854
5,912
California
Hi mate, I've just replied above about the CCC snapshots. Maybe you could take look at the screenshot. Its. huge amount of space!

I'm confused as to why I would need TM making constant snapshots, and CCC making snapshots too, and also why have them at all? They are stored on the same drive so if that fails they are all gone. But I'm backing up regularly to other drives with CCC and TM, so why isnt that enough? Is it just to save deleted files, or to restore to an earlier point in the last day or two? If so, I'm not sure its worth the space!

I'm a bit confused about what to do. thanks for everyones help, I feel I might be getting close to sorting it out!
@mikecwest did a great job explaining everything above.

They do snapshots to offload to external drives later. So, say I delete an important document because I don't think I need it - they "save" this temporarily so they can offload it to the external drive when I hook it up to an external drive. Also, this makes restoring that important document easy without needing my external drive there. It's a backup of a backup in a way.

I use both CCC and TM because my data is super important to me. I realize it's a bit redundant but you can't ever have too many backups. That and I have a 1TB SSD with only 180GB used so I don't mind the extra space used. I use CCC to delete large snapshots if I remove something large I don't need.

I've noticed that TM snapshots far more regularly than CCC does. But I'm no expert.

If I had a 256GB SSD or 128GB SSD, I'd only use one to snapshot and just use CCC to copy to an external drive without snapshots.
 
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kohlson

macrumors 68020
Apr 23, 2010
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314gb snapshot for CCC!
I realize you have been getting a lot of input, and in some sense this is like an old-time movie, with the train racing down the tracks toward impending disaster (you run out of disk space).

TM makes tries to keep "current" by making a local snapshot on a pretty regular basis. If the designated drive is not connected, it's kept on the startup disk until the backup disk is connected. In my experience these files are large-ish, but not terribly large. In any event I don't think TM local backup will consume all available disk space on the startup disk.

I used to use CCC, and one of the things I remember from it was (to me) the UI was confusing. This may no longer be the case. But - and I am just checking here - are the Source and Target volumes different?
 
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madrich

macrumors 6502
Feb 19, 2012
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The computer was new just a few months back. If you resin tall the OS, does it keep everything else, your installed programs and all your documents? ~Or do you have to reinstall everything . Sorry for the noob questions
If you reinstalled the OS then it erases everything else; unless you later use the migration assistant to import anything else.
 
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robodelfy

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Original poster
Jan 13, 2018
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The time machine local snapshots keeps a history of changes...Lets say you are working on a document, and say, "Gee, I wish I had left that file how it was on Tuesday." You can go "back in time" and recover it in that state.

Now the part that might shed more light on it for you, many people do not leave their backup drive connected all the time, or may not have one at all.

Ok, if you follow so far, you have basically a "running tab" or changes. These should be combined into your "time machine backup drive," each time that you connect it, at which time the "local backups" are removed.

A couple things could go wrong here, lets say you have your time machine backup on a hard drive you named "tacocat." You decided to re-partition that drive, and add an additional partition. OK, now you just altered the UUID of the drive, and time machine no longer realizes it is the same drive, and doesn't combine the local snapshots into the backup drive.

Lets say you just forgot to, intentionally did not, was too busy too, or maybe didn't know you needed to connect your backup drive, it won't get updated. Your local snapshot will get bigger and bigger.

As far as CCC snapshots go, I am assuming that CCC has a similar method of operation.

You can easily turn off time machine, or if you prefer to keep your backup, you can just plug in your time machine drive everynight, and let it synchronize while you sleep.

If you have a "Time Capsule," make sure it is setup properly.

Also, as far as having both CCC and TM backups at the same time, some people are paranoid about data loss, and might use two separate backup methods. If you do this, make sure that you attached both CCC and TM backup drives frequently to reduce the footprint of the "local snapshots."

You might turn off TM if you prefer CCC or vise versa. If you don't really care about data loss, turn off both.
Thanks, yeah I think I get it. I didn't realise that TM local snapshots were removed/moved when you plug in your TM drive to backup. I didn't notice this happen when I plugged in my drive.

And I'm sure the wasn't happening with CCC as I had plugged in my CCC drive and updated the clone many times, yet that huge 300gb snapshot was still hiding! I deleted it now, and it was very satisfying to watch all the space come back in seconds!

I'm still a little confused about what to do, whether to leave these snapshots on for both TM and CCC, or only one, and if so which as they seem to work differently.

I have 3 backup drives. 1 TM, and 1 CCC, that I keep with me when I travel, but leave at wherever I'm staying. Then one CCC drive back at my family home.

I do this because TM machine gives useful snapshots of the machine at various times, where as CCC just clones the drive and keeps any changed files in the safety net folder. So it's good to have both. CCC is so much faster as well, so I do that more regularly.

Who would have thought backing up would take so much energy :)
[doublepost=1536660313][/doublepost]
@mikecwest did a great job explaining everything above.

They do snapshots to offload to external drives later. So, say I delete an important document because I don't think I need it - they "save" this temporarily so they can offload it to the external drive when I hook it up to an external drive. Also, this makes restoring that important document easy without needing my external drive there. It's a backup of a backup in a way.

I use both CCC and TM because my data is super important to me. I realize it's a bit redundant but you can't ever have too many backups. That and I have a 1TB SSD with only 180GB used so I don't mind the extra space used. I use CCC to delete large snapshots if I remove something large I don't need.

I've noticed that TM snapshots far more regularly than CCC does. But I'm no expert.

If I had a 256GB SSD or 128GB SSD, I'd only use one to snapshot and just use CCC to copy to an external drive without snapshots.
Thanks, yeah I talked about some of this in my reply just now to someone else.

I also use both. I've deleted my CCC snapshot and recovered most of this space thank god! But now it hasn't created a new CCC snapshot, Im not sure when it will. I can see 4 TM ones in CCC, all created today and yesterday, but they are tiny, only 40mb each.Are you sure CCC shows all the TM snapshots? I just dont understand how they can be so small

thanks for the help everyone :)
[doublepost=1536660430][/doublepost]
I realize you have been getting a lot of input, and in some sense this is like an old-time movie, with the train racing down the tracks toward impending disaster (you run out of disk space).

TM makes tries to keep "current" by making a local snapshot on a pretty regular basis. If the designated drive is not connected, it's kept on the startup disk until the backup disk is connected. In my experience these files are large-ish, but not terribly large. In any event I don't think TM local backup will consume all available disk space on the startup disk.

I used to use CCC, and one of the things I remember from it was (to me) the UI was confusing. This may no longer be the case. But - and I am just checking here - are the Source and Target volumes different?
Thanks, you'll see in my other replies that it was one huge CCC snapshot, which I deleted. CCC interface is actually very simple, I didn't know about the sidebar which is where the snapshots were hiding. I'm still trying to work out exactly what to do with each program/backup.
 
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BigMcGuire

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Jan 10, 2012
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Yep. I deleted 20GB of a backup that I didn’t need anymore. This of course resulted in no returned space so I went into ccc and wiped out that snapshot. Doesn’t happen too often as most of the time the data I’m dealing with is a few meg at most.
 

mikecwest

macrumors 6502a
Jul 7, 2013
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Yep. I deleted 20GB of a backup that I didn’t need anymore. This of course resulted in no returned space so I went into ccc and wiped out that snapshot. Doesn’t happen too often as most of the time the data I’m dealing with is a few meg at most.
You might even have TM snapshots of your CCC Snapshots, and CCC Snapshots of your TM Snapshots....You might wasn’t to make sure that the TM snapshot is excluded from CCC backups, and that the CCC backup is excluded from TM backup, if not I can see you ending up with backup of backups of backups.....That could easily fill your drive.
 
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Fishrrman

macrumors P6
Feb 20, 2009
18,199
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I've kept cloned backups since I began using OS X.
I've NEVER used Time Machine -- and never will.
I've even removed TM's app and pref pane from my Macs.

Never lost data because of that backup strategy.
Never seen a "CCC snapshot". That's a good thing.
 
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BigMcGuire

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Jan 10, 2012
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I've kept cloned backups since I began using OS X.
I've NEVER used Time Machine -- and never will.
I've even removed TM's app and pref pane from my Macs.

Never lost data because of that backup strategy.
Never seen a "CCC snapshot". That's a good thing.
Forgive my ignorance if you've posted this elsewhere - I'm very curious as to what your backup strategy is. What do you use to clone your hard drive? Very interested. Thanks!
 

Fishrrman

macrumors P6
Feb 20, 2009
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"Forgive my ignorance if you've posted this elsewhere - I'm very curious as to what your backup strategy is. What do you use to clone your hard drive?"

I use CarbonCopyCloner and keep clones in various places.
That's about it.
 
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BigMcGuire

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Jan 10, 2012
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California
"Forgive my ignorance if you've posted this elsewhere - I'm very curious as to what your backup strategy is. What do you use to clone your hard drive?"

I use CarbonCopyCloner and keep clones in various places.
That's about it.
I've been leaning towards this too and will most likely do it as well. No need to have double backups! I really like CCC and am a very happy customer. Thanks for the info.
 

gr8pics

macrumors regular
Jan 20, 2008
171
4
Same problem here, as of the past two OS versions.
It just to work 15 years prior to this, no it takes 10-15 mins before the updated space shows after emptying the trash.
Is it a new annoy feature, since Apple choose not to fix it?
 

tillkrueger

macrumors newbie
Dec 1, 2013
6
4
I know this is an old thread, but I have been having the same problem for what seems like at least 2-3 years (definitely on Mojave and now Catalina).

I have fully committed to Catalina now, after doing a completely fresh install from scratch to rule out any left-over gunk from my years-old work-environment and trying to create as lean a system as possible (as close to 200GB as possible with *everything* installed), and after hitting 280GB and analysing my 1TB SSD/NVMe (MBP 2018) I found my Logic samples taking up nearly 80GB...I created some sim-links and moved them to my external SSD, but Catalina just wouldn't release those 80GB, no matter what I did...emptied trash, of course, waited for hours, rebooted a few times.

Since I had done a full backup right before installing Logic and all those samples (anticipating that I'd go way over my 200GB allowance), I decided to prepare for a system restore and backed up the system one more time with Carbon Copy Cloner, *after* removing those 80GB and just to be safe, and strangely enough, right after CCC finished its full backup, the available space on my internal NVM jumped back to 800GB!

What's up with that? Does CCC change/fix anything relating to how Finder calculates free space?

But that wasn't the end of it...I proceeded to install UnrealEngine 4 (both 4.23 and the new 4.24 preview), which took up over 40GB of space, before deciding that I should have installed the engines to the external SSD, so I proceeded to uninstall them, only to find that the space wasn't released afterwards *again*!

I did yet another backup with those two engines un-installed, and the CCC backup read out as about 180GB (CCC did *not* release the missing space of my system this time, though).

So then I rebooted into Recovery, formatted my internal NVM, restored from the CCC backup, and when I logged back in, lo-and-behold, my System showed 800GB of free space again.

What could be causing this erratic Finder behaviour regarding available space?
Is there some terminal command I should execute to re-index the part of Finder that reports available space, and if so, what is it?

Phew! sorry for the long-winded post, but I have scoured the interwebs far and wide and for years, and I think that this needs to be discussed, so that others who have the same issue can hopefully find this thread and know that they are not alone...and maybe even read about what this is caused by and how to avoid it happening...without having to backup and restore their system :-/
 
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Jaya Lin

macrumors newbie
Dec 12, 2019
1
0
I know this is an old thread, but I have been having the same problem for what seems like at least 2-3 years (definitely on Mojave and now Catalina).

I have fully committed to Catalina now, after doing a completely fresh install from scratch to rule out any left-over gunk from my years-old work-environment and trying to create as lean a system as possible (as close to 200GB as possible with *everything* installed), and after hitting 280GB and analysing my 1TB SSD/NVMe (MBP 2018) I found my Logic samples taking up nearly 80GB...I created some sim-links and moved them to my external SSD, but Catalina just wouldn't release those 80GB, no matter what I did...emptied trash, of course, waited for hours, rebooted a few times.

Since I had done a full backup right before installing Logic and all those samples (anticipating that I'd go way over my 200GB allowance), I decided to prepare for a system restore and backed up the system one more time with Carbon Copy Cloner, *after* removing those 80GB and just to be safe, and strangely enough, right after CCC finished its full backup, the available space on my internal NVM jumped back to 800GB!

What's up with that? Does CCC change/fix anything relating to how Finder calculates free space?

But that wasn't the end of it...I proceeded to install UnrealEngine 4 (both 4.23 and the new 4.24 preview), which took up over 40GB of space, before deciding that I should have installed the engines to the external SSD, so I proceeded to uninstall them, only to find that the space wasn't released afterwards *again*!

I did yet another backup with those two engines un-installed, and the CCC backup read out as about 180GB (CCC did *not* release the missing space of my system this time, though).

So then I rebooted into Recovery, formatted my internal NVM, restored from the CCC backup, and when I logged back in, lo-and-behold, my System showed 800GB of free space again.

What could be causing this erratic Finder behaviour regarding available space?
Is there some terminal command I should execute to re-index the part of Finder that reports available space, and if so, what is it?

Phew! sorry for the long-winded post, but I have scoured the interwebs far and wide and for years, and I think that this needs to be discussed, so that others who have the same issue can hopefully find this thread and know that they are not alone...and maybe even read about what this is caused by and how to avoid it happening...without having to backup and restore their system :-/

Some ideas.

I had the same problem, the "disk almost full" message came up repeatedly. I deleted 30GB of space but only about 2GB seemed to come back as "available" space.

However I later tried deleting more space, and this second bit of freed up space did all show up in my available space count. To be clear, the 30GB initially deleted never came back, but the 10GB I deleted second time around, that did come back.

What might be happening is the system "likes" to use the SSD for temporary storage of caches and such things, but as the disk gets fuller it puts that stuff as second priority. When I deleted 30GB the system suddenly thought "Woohoo, free space!", and quickly filled up that newly freed up space with caches, indexes and such things that make the system work smoother.

Or perhaps the system had some of its working files compressed and it uncompressed them as soon as there was space. But the result is the same, I.e., the system might have simply used up the first lot of newly freed up space for its own purposes as soon as we freed it up.

One way to check might be like a previous poster wrote: Go to About This Mac: Storage. Look at the breakdown of disk usage before and after you free up some space. You might see documents, photos, apps etc adding up correctly, and only "system" increasing in size. That would prove the system is just grabbing that space, which would solve the mystery of the missing space.