A 100 MiB sparse file occupying 16 KiB was copied with cp, cat, ditto, rsync and rsync -S. The results ranged from 0 KiB to 102,400 KiB. Every copy was byte-identical to the source and every one reported the same size to ls.
A census of every launchd job on one MacBook Pro found 533 registered, 262 with a live process, and 271 sitting dormant. 202 of them last ended on SIGKILL by design rather than by failure, and the total itself drifts during a session as applications register and withdraw their own entries.
The memory compressor is doing 2.58 to 1 on live data right now, and it is the reason Apple can ship machines with memory configurations that look too small on paper. Here is the ratio, measured.
How one piece of Apple’s system actually behaves
A census of every launchd job on one MacBook Pro found 533 registered, 262 with a live process, and 271 sitting dormant. 202 of them last ended on SIGKILL by design rather than by failure, and the total itself drifts during a session as applications register and withdraw their own entries.
A task run end to end, timed
A single Activity Monitor glance tells you nothing, because the numbers move constantly. A 0.52 second script that logs the four figures that matter turns guesswork into a trend line.
One failure, its exact error text, and the fix
Every Linux answer wraps long-running commands in timeout. macOS has never shipped it. Four replacements, and the one that behaves correctly when the command exits on its own.
A claim put on the clock
A 100 MiB sparse file occupying 16 KiB was copied with cp, cat, ditto, rsync and rsync -S. The results ranged from 0 KiB to 102,400 KiB. Every copy was byte-identical to the source and every one reported the same size to ls.
MacBook Pro Apple M4 Pro