Caliper 0.1.2

Caliper's history charts were drawing things nobody measured. This fixes that,
which is the whole of the release.

What changed

• A gap in the record now looks like a gap. A bucket is written only when
  the Mac is awake to be measured, so a night's sleep leaves a hole — and the
  chart used to join the two edges of it with a straight line and fill the
  min/max band underneath. On this machine that turned sixteen hours of nothing
  into a smooth ramp on the disk and network plots. The line now breaks where
  the record breaks, and a stretch of one lone bucket is marked with a point
  rather than vanishing.
• The one-hour view shows its top processes again. It had been asking the
  process log for the half-minute the cursor was standing in, which is usually
  still being written; it now takes the newest half-minute that was, and says
  which one it is showing. With recording switched off it goes back to showing
  nothing, which is the point of the switch.
• A chart stays inside its card. The temperature panel's shading was drawn
  past the bottom of its card and over the readings underneath — it was filling
  from zero, and that chart's scale starts near body temperature.

About the numbers

"Under 1 % of one core" is the steady state — menu bar up, nothing open. A
panel costs more while it is open, around 2 %, because it samples and draws
what it shows. Both figures are shares of one core, the unit Activity
Monitor's %CPU column uses, not of the whole machine.

Requirements

macOS 15 or later, Apple Silicon. Sensors are read on a best-effort basis: what
a particular Mac will not report is hidden rather than guessed at.

Caliper 0.1.1

A performance release. Caliper cost the most in the one state you were most
likely to be looking at it — a panel open, which is the only way to read its
own figure. That is fixed, and the claim it makes about itself is now specific
about which state it describes.

What changed

• A panel only samples what it shows. Cadence used to be decided by how
  much of the app was open, so opening any panel pulled the temperature sweep
  from one reading every thirty seconds to one every two — including on the
  four panels that draw no temperature at all. That sweep is the most expensive
  reading Caliper takes, by an order of magnitude. Each surface now asks for
  the metrics it actually draws and nothing else.
• The menu bar stopped repeating itself. The strip was handing the window
  server a new label, tooltip and width on every refresh whether or not any of
  them had changed, and a module with nothing to show — a Mac that reports no
  sensors — was being re-hidden twice a second for the life of the session.
• The disk image is an installer now. It opens with Caliper and the
  Applications folder side by side, so the instruction to drag one onto the
  other is finally something you can follow — until now the image held the app
  and nothing else, and you had to go and find Applications yourself.
• On this Mac, with the default strip: 0.68 % of one core with the menu bar
  alone, down from 0.78 %, and 2.1 % with the CPU panel open, down from 3.2 %.
  Closing a panel now returns to where it started instead of settling at twice
  it.

About that number

"Under 1 %" is the steady state — menu bar up, nothing open — and it was never
a claim about anything else. Since the only way to see Caliper's own reading is
to open a panel, the expensive state is the one everybody meets, so the figures
above name which is which. They are shares of one core, the unit Activity
Monitor's %CPU column uses, not of the whole machine.

Requirements

macOS 15 or later, Apple Silicon. Sensors are read on a best-effort basis: what
a particular Mac will not report is hidden rather than guessed at.

Caliper 0.1.0

The first release of Caliper — a native macOS system monitor that lives in the
menu bar, keeps a real history of what the machine has been doing, and is built
not to become the load it measures.

In this build

• Menu bar — CPU, memory, network, disk and temperature, each drawn at a
  fixed width so nothing shoves its neighbours around. Every module is
  configured on its own: the picture is its live graph, the symbol that names
  it, or nothing, and the value switches on and off beside it. The modules can
  also share a single item, in an order you set by dragging.
• Panels — one behind each module. CPU with its performance and efficiency
  clusters, per-core bars and the heaviest processes; memory pressure and
  composition; disk throughput, free space and drive health; network rates with
  the interface and address behind them; every sensor and fan the machine will
  report.
• History — recorded locally to SQLite from the moment the app starts,
  rolled up 10 s → 1 min → 10 min → 1 h, and charted over an hour, a day, a
  week, a month or a year. Nothing leaves the Mac.
• Cost — under 1 % of one core and under 50 MB of physical footprint in
  menu-bar-only use, measured by a harness rather than hoped for.
• Updates — Caliper now checks for its own, quietly: a scheduled check that
  finds something marks the menu bar rather than interrupting you, and every
  update is verified against the developer signature before it is applied.

Requirements

macOS 15 or later, Apple Silicon. Sensors are read on a best-effort basis: what
a particular Mac will not report is hidden rather than guessed at.

Installing

Open the disk image and drag Caliper to Applications. The build is signed with
a Developer ID and notarized by Apple, so it opens without a warning.