Overview Tab¶
The Overview tab (tab 1) is the default landing view. It provides a real-time dashboard of key system metrics with sparkline history graphs.
Layout¶
The Overview tab is divided into several sections, arranged to fit within the terminal window:
- CPU -- per-core gauges, aggregate usage, clock frequency, sparkline
- Memory -- RAM and swap usage with gauges and sparkline
- Thermal -- SoC temperature with sparkline
- Network -- per-interface throughput rates
- GPU -- frequency, memory, temperature, codec status (Pi-specific)
- Fan -- RPM and duty cycle (Pi 5 only)
CPU section¶
Displays real-time CPU utilization parsed from /proc/stat.
- Per-core gauge bars show individual core utilization as percentage bars
- Aggregate usage is the average across all cores
- Current frequency is read from
/sys/devices/system/cpu/cpufreq/ - Sparkline plots the last 60 samples (configurable via
history_size) of aggregate CPU usage
Color coding¶
| Color | Meaning |
|---|---|
| Green | Below warning threshold (default: < 60%) |
| Yellow | At or above warning threshold (default: >= 60%) |
| Red | At or above critical threshold (default: >= 85%) |
Memory section¶
Shows RAM and swap usage parsed from /proc/meminfo.
- RAM gauge displays used / total and percentage
- Swap gauge displays used / total and percentage (hidden if no swap is configured)
- Sparkline tracks RAM usage percentage over time
Color coding¶
| Color | Meaning |
|---|---|
| Green | Below warning threshold (default: < 70% RAM, < 25% swap) |
| Yellow | At or above warning (default: >= 70% RAM, >= 25% swap) |
| Red | At or above critical (default: >= 90% RAM, >= 50% swap) |
Thermal section¶
Displays SoC temperature from thermal zones in /sys/class/thermal/.
- Temperature reading in degrees Celsius
- Sparkline tracks temperature history
On Pi 5, additional thermal zones may appear for the PMIC and RP1 southbridge.
Color coding¶
| Color | Meaning |
|---|---|
| Green | Below 60C |
| Yellow | 60C -- 74C (warning range) |
| Red | 75C+ (critical) |
Throttling
If the SoC temperature reaches the critical threshold, the Pi firmware may throttle the CPU to reduce heat. Check the throttle indicator in the header bar.
Network section¶
Shows per-interface throughput rates parsed from /proc/net/dev.
- Download rate (RX bytes/sec) for each interface
- Upload rate (TX bytes/sec) for each interface
- Sparklines for each interface's RX and TX history
The loopback interface (lo) is filtered out by default.
GPU section¶
Displays GPU data collected via vcgencmd:
- Core frequency in MHz (from
vcgencmd measure_clock core) - Memory allocation in MB (from
vcgencmd get_mem gpu) - Temperature in Celsius (from
vcgencmd measure_temp) - Codec status showing whether H264 and HEVC hardware decode is enabled
Note
GPU data is only available on Raspberry Pi boards with vcgencmd installed. On other systems, this section is hidden.
Fan section (Pi 5 only)¶
Displays fan speed data from the hwmon subsystem:
- RPM -- current fan speed in revolutions per minute
- Duty cycle -- PWM duty as a percentage (0--100%)
This section only appears on Pi 5 boards with the official fan connected. The fan hwmon device is discovered dynamically by scanning /sys/class/hwmon/ for a device named cooling_fan.
Throttle indicator¶
The header bar shows a throttle status indicator:
- Green -- no throttle events detected
- Yellow -- throttle events occurred in the past but are not currently active
- Red -- active throttling is occurring right now
Throttle data comes from vcgencmd get_throttled, which reports a bitmask covering under-voltage, frequency capping, and thermal throttling.