Unlimited Activity

Every process on your Mac, and what it costs.

Mac

Coming soon for Mac.

Activity is a process monitor with the density of command-line tools and the manners of a Mac app. It reads the process table once a second, shows more columns as you widen the window instead of shrinking the ones it has, and then a handful of numbers no other monitor shows.

Six numbers no other monitor shows

• Effective clock — how fast a process actually ran, from its own cycle counter divided by its own CPU time. Not the machine’s nominal speed.
• Instructions per cycle — two processes at the same CPU % can be doing very different work. Low means stalled on memory.
• Power in milliwatts — real energy from the kernel, not a weighted “impact” score. The same work in the background costs about a fifteenth as much, and the number shows it.
• Wait — milliseconds per second a process was ready to run but didn’t, because every core was busy. That is the number behind a slow Mac whose CPU graph looks fine.
• Quality of service — which of the kernel’s seven classes this second of CPU went to, as a stacked bar with the dominant class in words.
• Fast-cluster share — how much of a process’s time landed on the machine’s quickest cores.

And the machine itself: hottest CPU, GPU and memory sensors, every fan, battery health, cycle count, signed watts and pack temperature. Those aren’t in a terminal monitor either.

Why is my computer slow?

Nobody opens a process monitor to read thirty-five columns. They open it because something feels wrong. The Summary answers in sentences — the processor is busy, threads are waiting for a core, the clock is being held down, pages are coming in from disk, the fans are working against heat the processor is not producing. Those look the same on a CPU graph. Telling them apart needs wait, effective clock and real watts.

• Every finding names the number it came from, so you can check it.
• It never guesses from a blank. About a quarter of the table can’t be measured, so no rule fires on “the CPU is busy but nothing is using it”.
• “Nothing is holding this Mac back” is a finding too — and the one you will see most often.

The table

• Sort by any column, click again to reverse. A row the kernel will not measure sorts last, either way.
• Filter by name, path, user or exact pid, with Mine and Active switches beside the field.
• Watch a process with ⌘D and it stays pinned at the top while everything else keeps re-sorting.
• Widen the window and more columns appear, every one full size. Drag a heading to reorder; a narrow window drops columns in that same order.
• Freeze with Space when you need the table to hold still.

One process, in full

Click a row and the inspector tells you what that process is doing right now, then everything the kernel will say: the family tree from launchd down, the command line, the working directory, the environment, and every file, socket, pipe and port it holds. Send any of the 21 signals. Quit, Pause and Resume are one click.

Ports and open files

• What lsof reads, with the owning process named — every socket with both ends and its TCP state, and every open file by kind and path.
• Listening only — the fastest answer to “what is on port 8080”.
• Who is my Mac talking to — the Network pane groups live connections by host.
• macOS does not report network bytes per process, so Activity does not invent a number for it.

An em dash is never a zero

macOS only reports measurements for processes you own. On a normal Mac that leaves about a quarter of the table — system daemons and other people’s processes — named but not measured. Those rows carry a lock, every derived number is an em dash, they sit out of the rankings, and the strip at the top says how many there are, so every total on screen is a lower bound. There is no helper, no root, nothing to install.

On your Mac

• Four rooms on a rail — Summary, Processes, Resources, Ports — on ⌘1 to ⌘4; CPU, Memory, Energy, Disk and Network on ⌘5 to ⌘9.
• Columns, their order, the sort and the interval survive a restart.
• Bigger type is one keystroke. Full keyboard navigation, and a Help book.
• Very lightweight — only milliseconds to read the process table, so the monitor itself stays out of the way.

One purchase