Reclaiming lost space on an SSD

There is an enormous amount of OLD and unreliable information on the Internet, and possibly right here on this forum, about TRIM. The particular text you mentioned raises a semi-valid point about previously-deleted Blocks and TRIM.

There is a straightforward solution:

Once you enable TRIM, every deleted block released in the future will be called out to the drive controller as it is deleted. This setting is stored on the MacOS Boot Drive. To eliminate previously-deleted blocks after enabling TRIM, Restart in Safe Mode. Safe Mode does a pass of disk Utility repair Disk/first aid, while honoring the setting of TRIM. Near the end of its process, the log says "TRIM-ing unused blocks" and the test pauses, possibly for a minute or more while they are removed.

The fundamental issue with very high reported usage in any particular area is that these estimates are based on the Spotlight Index. Spotlight does not always reflect deletions and re-installs, so its information can tends to "drift" and the estimates get further off courses more time elapses.

To get them more accurate, re-create the spotlight index:

How to rebuild the Spotlight index on your Mac - Apple Support

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Want to know about Time machine snapshots? read THESE articles:

About Time Machine local snapshots - Apple Support

.Pondini's Time Machine - Frequently Asked Questions -- 30. What are Local Snapshots?

And to make sure that you have storage space when you need it, snapshots are stored only on disks that have plenty of free space. When storage space gets low, additional snapshots are deleted, starting with the oldest. That's why Finder and Get Info windows don't include local snapshots in their calculations of the storage space available on a disk.

If you are running High Sierra using Apple File System (APFS) , these snapshots take up incredibly small amounts of space.They do not contain duplicate copies of the files at all, just a whole lot of pointers to files.

Thank you for the info. What is your issue with CleanMyMac? I just want to make sure there isn't a huge issue I'm unaware of.

We see numerous posts here at the ASC with folks having issues with their Macs around using cleaner apps, like CleanMyMac. In almost all cases, the recommendation is to completely remove these apps as they are not necessary. The macOS operating system is very efficient at keeping things "tidy" and we find that these third-party apps cause more issues than they resolve ... especially with getting rid of them.

CleanMyMac is unrelenting GARBAGE.

• Your Mac does not accumulate anything that needs to be cleaned, and if it did, Apple would ship a cleaner App in the box.

• Deleting the caches most of these so-called cleaners target will make your Mac slower, not faster.

• This specific package has a reputation for tossing out important parts of MacOS while it does its supposed "cleaning". Readers who used it have been forced to Re-install MacOS for no other reason than it has been "cleaned" with CleanMyMac.

Do not intervene with ANYTHING to do with Time Machine, or you face losing data and losing Trust in your backup. If too many temporary backup files are accumulating, it is time to connect your backup drive and let the backup run, NOT time to start trying to delete things.

YouTube contains huge amounts of Wasted Space used to record things that should never be conveyed with Video, using horrible cinema techniques, consisting of marginal or wrong information. But worst of all is that there is no adjudication of what is good and what is rubbish. You should be far, far more skeptical of the media you consume.

That Video appear to have been made by someone with no special knowledge of the subject, and no special skills in making Videos. It is full of incorrect assumptions and guesses. Do not do ANYTHING that guy suggests -- his information is WRONG and his solutions are NONSENSE.

If I make an outrageously wrong statement here, there will be a Pig Pile on top of me before this time tomorrow. At least on these forums, Nonsense does not stand.

First, I suggest that you completely remove CleanMyMac from your notebook. Second you should enable TRIM for your SSD. Finally, take a look at the following articles to see if they can help you with gaining additional storage space:

• What is 'Other' and 'Purgeable' in About This Mac? - Apple Support
• Free up storage space on your Mac - Apple Support