How to delete Time Machine local snapshots in macOS | AppleInsider

2022-05-14 23:24:41 By : Mr. Dave jin

Copyright © 2022, Quiller Media, Inc.

AppleInsider is supported by its audience and may earn commission as an Amazon Associate and affiliate partner on qualifying purchases. These affiliate partnerships do not influence our editorial content.

Apple's Time Machine is an essential file backup tool for macOS, but it too has a backup that works off your Mac's primary drive. Here's how Time Machine's local snapshots work, and how to get rid of them if you want them gone.

Most Mac users are very familiar with Time Machine, Apple's fantastic utility for keeping multiple copies of files backed up and accessible within minutes. Many will have favorable opinions of the tool, especially after using it to rescue an accidentally deleted, edited, or corrupted file that's urgently needed for a task.

It's likely that many people think that Time Machine also only uses an external drive to house the files, but this isn't quite true. In fact, part of its functionality takes place on the primary storage of the Mac, in a feature called local snapshots.

This use of local storage may be concerning to those who juggle large files regularly, but it's far from a concern for the vast majority of the users.

Here's how Time Machine local snapshots work and use storage.

The usual explanation for how Time Machine works is that it makes a copy of all files, or files that have changed since the last recorded backup, and save them to a backup drive. With successive backups of changed files, this can create an adjustable snapshot of the files on the Mac at various times in the past, which can be accessed and used if required.

On top of this main backup to the external drive, Time Machine creates a second version, referred to as local snapshots, which are stored on the primary drive of the Mac instead of the external drive.

The local snapshots are effectively the same hourly backups, in that they retain file changes that occurred over the last hour. Typically this locally stored backup consists of hourly snapshots of the primary drive for the last 24 hours, but it also keeps a snapshot of the last successful Time Machine backup performed with the external backup drive.

The main reason for Time Machine storing hourly local snapshots on the user's drive is for connectivity. While using an external drive for backups makes sense, there's no guarantee that the drive will be available to use.

If the cable's been pulled, the drive needs to be powered off and on to get out of a funk, is stolen, or stops working entirely, the Mac's simply not going to be able to make its regular Time Machine backup.

If you were to try and access Time Machine's backups when the external disk is unavailable, you're not going to have the full catalog of backups to view or search through. Instead, Time Machine will just show the hourly local snapshots, and leave out the older backups from the list.

To end-users, this basically means there's a persistent hourly backup available covering a 24-hour period. This may not be as useful as the full catalog, but if you're in a pinch over a file that you need to resurrect from a few hours ago, you're still covered.

When the Mac is able to reestablish a connection to its backup drive, the full backup catalog will be available once again.

Since Time Machine uses the internal disk to store its local snapshots, it's worth asking if this can affect your usable storage capacity on your Mac. Sure, storage does get consumed, but to users, it's done in such a way as to be as unobtrusive as possible.

The hourly backups and the last proper backup will only exist on a Mac if there's storage capacity available. If there's no storage capacity available to use, then Time Machine will retain the most recent snapshots and automatically get rid of the older ones.

However, for the purposes of how it is stored on the Mac itself, macOS categorizes the local snapshots as available storage. That is, the operating system considers the capacity used for local snapshots to be spare capacity that could be used by the user to store files since it can delete older snapshots.

If you're constantly changing large files or high quantities of documents, then each of these snapshots will take up more space individually. While this will mean a smaller number of snapshots in instances where there's limited remaining storage capacity, they're still all files that can be removed if the system needs the space.

As an essential element of how Time Machine works, you can't stop it from creating local snapshots, short of turning off Time Machine completely. That being said, you can get rid of the local snapshots manually.

This isn't really necessary as the way that macOS deletes local snapshots will still keep storage free, but the option is still there.

If you want to get rid of all local snapshots, the process is quite simple.

This will remove all currently accessible local snapshots, but it will take some time for macOS to complete the process. There's also no interface to tell you if the local files are deleted, so you can only try to access the backup with the external drive disconnected to check their status

You can also go through the same process in a more manual fashion, but this requires using Terminal.

If you want to delete many or all snapshots, the best option is to use the first method, then use the listlocalsnapshots Terminal command to check they're gone.

Keep up with everything Apple in the weekly AppleInsider Podcast — and get a fast news update from AppleInsider Daily. Just say, "Hey, Siri," to your HomePod mini and ask for these podcasts, and our latest HomeKit Insider episode too. If you want an ad-free main AppleInsider Podcast experience, you can support the AppleInsider podcast by subscribing for $5 per month through Apple's Podcasts app, or via Patreon if you prefer any other podcast player.

Keep up with everything Apple in the weekly AppleInsider Podcast — and get a fast news update from AppleInsider Daily. Just say, "Hey, Siri," to your HomePod mini and ask for these podcasts, and our latest HomeKit Insider episode too.

If you want an ad-free main AppleInsider Podcast experience, you can support the AppleInsider podcast by subscribing for $5 per month through Apple's Podcasts app, or via Patreon if you prefer any other podcast player.

If you've got an active subscription to Apple Music, you can play your favorite songs, artists, albums, and playlists right on your Apple Watch — and thanks to watchOS 8, now you can do even more.

You've still got all the tools to manage Mac notifications in macOS Monterey, but the introduction of Focus Mode means they've been rearranged - and improved.

If you're lost in a sea of icons and can't find the app you want, you may have too many pages of apps on your Home Screen. Here's how to switch the pages around and get rid of extra ones, in iOS 15 and iPadOS 15.

Google's introduction of the Pixel 6a pits its latest Android smartphone squarely against Apple's iPhone SE, but is it enough to pull away potential iPhone buyers over to the other side?

Alogic's first monitor, Clarity, echoes Apple's styling in many ways. While the Studio Display has incredible picture quality, Alogic aims for more flexibility.

The Razer Blade 14 has been updated for 2022 to make it more powerful, but it has to fight with the 14-inch MacBook Pro as a creator's choice notebook. Here's how the two laptops compare.

Stop using the same password for all of your accounts and secure your online life properly, by using a password manager. Here's some of the best for your digital protection.

Apple offers users a choice of a 13-inch MacBook Pro and a 13-inch MacBook Air for the entry-level model in its notebook line, but is there much difference between the two lines for the everyday user? Here's what it means to those new to Mac to go Air or Pro at the value end of the range.

Netflix could follow Apple TV+ in producing live streaming video

Compared: Apple 2022 iPhone SE vs Google Pixel 6a

Samsung prepares to raise chip production prices by up to 20%

How to play and share Apple Music on the Apple Watch in watchOS 8

Kendrick Lamar sets record for most first-day Apple Music album streams for 2022

iPhone supplier Pegatron issues production warning over COVID lockdowns

Compared: USB 3, USB 4, Thunderbolt 3, Thunderbolt 4, USB-C - what you need to know

Daily deals May 14: $409 iPad mini, $429 iPad, $290 18TB WD Elements external drive, more

If you've got an active subscription to Apple Music, you can play your favorite songs, artists, albums, and playlists right on your Apple Watch — and thanks to watchOS 8, now you can do even more.

You've still got all the tools to manage Mac notifications in macOS Monterey, but the introduction of Focus Mode means they've been rearranged - and improved.

If you're lost in a sea of icons and can't find the app you want, you may have too many pages of apps on your Home Screen. Here's how to switch the pages around and get rid of extra ones, in iOS 15 and iPadOS 15.

Using the Shortcuts app on your iPhone, you can automate common tasks with just a tap. Here are some useful ideas from logging your coffee consumption to starting your workout.

Apple's 79-pound iPhone Self Repair Program toolkit is on our test bench. Here's what's inside the hefty repair package.

The "iPhone 14" lineup is expected to be incredibly similar to the iPhone 13 with minor changes like camera performance and a new larger "max" model. Here's what the rumor mill suggests the phones will look like.

Apple claims that it has made significant improvements to the webcam included on the Studio Display thanks to a forthcoming update. We put the beta update to the test to see whether it notably improves Apple's much-criticized webcam.

Samsung is adding one new SSD to its T7 line. Joining the standard T7 and the T7 Touch is the all-new Samsung T7 Shield which boasts expanded durability and resistance compared to its siblings.

The Monoprice 28-inch CrystalPro 4K monitor looks like a competitive budget monitor on paper, but audible coil noise and poor design ruin its potential.

Tronsmart's new Bang speaker can pair with up to 100 other Bang units to fill a large space with sound, but there are several spots where the speaker could see improvement.

Customize your mood lighting with Govee's Hexa, a modular, wall-mounted RGBIC lighting fixture that could fit in practically anywhere in your home.

Casetify has started accepting orders for its first-ever Star Wars collection. We got to test a few of the products early, including a pair of iPhone cases.

Apple's keyboards are pretty good, but an excellent option for your Mac Studio or Mac mini is the Satechi X3 Slim — and it costs a lot less than Apple's too.

AppleInsider is one of the few truly independent online publications left. If you love what we do, please consider a small donation to help us keep the lights on.

If you love AppleInsider and want to support independent publications, please consider a small donation.