plottypus vs btop

At a glance#

Checked 2026-09-24 on a MacBook Pro Mac17,8 (M5 Pro, 6 Super + 12 Performance cores, 20-core GPU), macOS 27.0, btop 1.4.7 from Homebrew with a fresh config.

Sources: btop 1.4.7 release, btop README, btop’s key list, btop’s macOS collector. The btop screen readings are from our own capture at 160×45 on the machine above.

What btop shows on an M5 Pro#

btop’s CPU box lists the 18 cores as C0 to C17, each with a load bar and a temperature. It does not say which six are Super cores, and it shows no clock for any of them. On a Mac with two kinds of core that matters: a core at 100% and 1.3 GHz is doing a fraction of the work of one at 100% and 4.4 GHz.

The GPU line shows load, memory in use and power, and the GPU box (5) adds a clock. Its temperature read 0°C on our M5 Pro; plottypus read 74–75 °C for the same GPU a few minutes earlier. btop tracks this as issue #1653, open on 2026-09-24. Its network download rate reading 0 B/s on recent macOS is issue #1850, also open.

plottypus puts the clusters first. Here is one sample from plottypus --json with every core busy:

"clusters": [
  {"kind": "performance", "cores": 12, "usage": 1.0, "scaled": 1.0,  "freq_mhz": 4380},
  {"kind": "super",       "cores": 6,  "usage": 1.0, "scaled": 0.948, "freq_mhz": 4368}
]

usage is the share of time the cores were busy; scaled weights it by clock, so a cluster idling along at a low frequency does not look as busy as one at full speed.

Watts#

btop 1.4.7, the latest release (1 May 2026), shows GPU power on Apple Silicon: #1541 added a GPU backend that reads IOReport’s GPU Energy channel. It shows no CPU power on macOS. The CPU power readout it gained in 1.4.5 (#1227) is wired up in the Linux and BSD collectors only, and the 1.4.7 macOS collector never turns it on. plottypus reads CPU power without sudo. On the M5 Pro it comes from the SMC’s CPU power rails, calibrated against IOReport. On other chips it comes from IOReport’s CPU Energy counter, divided by the driver’s own timestamps rather than by the sampling interval. On macOS 27 that counter publishes in batches seconds to minutes apart, so plottypus holds the last batch, marks it ≈ with its age, and shows — once it is more than 10 s old. It never shows a made-up 0.

System watts (the SMC PSTR key), GPU watts and, when the counters publish, ANE and DRAM watts sit beside it.

Cost of leaving it open#

Both tools only repaint when something changed: 0 idle redraws each. Measured with our perf-smoke.py script (160×45 pty, fresh config, medians of three 20 s windows, M5 Pro, macOS 27, 2026-09-23):

The btop runs and the plottypus 1.0.0 runs were taken hours apart on a machine with other builds going, so treat differences under about 0.3 points as noise. At its own defaults btop is a little cheaper, because it samples a quarter as often.

Processes#

Both have a filterable, sortable process table with a tree view, a details pane and signals. btop has per-process mini graphs and “follow process”. plottypus adds, per process:

• energy in watts (the kernel’s per-task estimate), GPU share, disk I/O and wakeups;
• footprint memory, the figure Activity Monitor calls Memory;
• STOP/CONT, renice and a background-QoS toggle in the details card;
• a kill refused if the pid has been reused since you selected it.

Without sudo, macOS will not describe other users’ processes. plottypus shows — in those cells rather than a zero.

Scripting#

btop is interactive only. plottypus prints the same data as JSON, using macmon’s field names where they exist:

plottypus --json | jq '{cpu_power, gpu_power, sys_power}'
plottypus --json-stream --count 60 -i 1s > build.ndjson
plottypus --diagnose        # "Busy: rustc using 9.1 cores" plus the evidence

Switching from btop#

plottypus ships a btop key profile. Turn it on in any of three ways:

PLOTTYPUS_KEYS=btop plottypus       # this session only

# ~/.config/plottypus/config.toml
keymap = "btop"

or s → keys → key profile inside the app. The help screen (?) follows the profile you pick.

Watch t and k. In btop they send signals; in this profile they toggle the tree and move the selection up, and every kill goes through x, K or the signal picker, each behind a y/n prompt.

Two config lines that make plottypus feel closer to btop’s defaults:

interval_ms = 2000        # btop's update_ms default; accepts 250, 500, 1000, 2000 or 5000
glass = "on"              # like theme_background = false: never paint a cell background