As Time Machine has changed, first to back up APFS volumes, then to create backups as snapshots, its needs have changed. This makes it complicated to decide which local snapshots you can delete without affecting its backups.
free space
It was notorious for its crashes and reporting discrepancies, but now it’s incorporated in System Settings it’s more reliable and helpful. But there’s still the problem of System Data.
Why upgrading to Tahoe shouldn’t consume the last free space on your Mac’s SSD, and once it has settled should use little more than currently. How to clear out old snapshots and reduce System Data.
What do you do when you discover your Mac’s Data volume has run out of free space? A guide to working with snapshots, iCloud Drive, and other tricks to salvage your Mac. And how to prevent this from happening again.
Speed up your hard disk by partitioning it so that its innermost 20% remains unused. Reserve space for the SLC write cache on an SSD by limiting the size of volumes.
When it started up after its macOS update, available space on its internal SSD had shot from about 160 GB to nearly 400 GB. Where had all my files gone?
The bar chart in Storage Settings shows most of your startup volume is full of System Data. What does it mean, and what use is it? Is its measure of used and free space accurate?
Knowing a little about sparse and clone files in APFS is dangerous, as it can lead you to draw the wrong conclusions.
How much free disk space could you recover if your Mac is short of space and you need more to upgrade to Sonoma? Should you try flushing its caches in Safe mode?
Should you just try to upgrade in the hope that your Mac’s storage has sufficient free space? What can you do to free up a bit more if needed?
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