---
id: TASK-025
title: 'TUI: Per-core CPU bars on System page'
status: To Do
assignee: []
created_date: '2026-06-12 04:21'
labels:
  - tui
  - feature
dependencies: []
priority: low
ordinal: 25000
---

## Description

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The System page shows aggregate CPU% but no per-core breakdown. Add a per-core bar section to the CPU panel or as a new row between the sparkline and the process table.

Implementation:
- `psutil.cpu_percent(percpu=True)` returns a list of per-core percentages
- Add this call to `SystemStats.sample()` → `"cores_pct": [...]`
- Render as a grid of labeled bars: `C0 [████░░░░]  42%  C1 [██░░░░░░]  18%  …`
- Use Unicode block chars (`█`, `░`) for bars, scaled to a fixed width (e.g. 8 chars)
- Color: green < 50%, yellow 50–80%, red > 80%
- Layout: 2 or 4 cores per row depending on terminal width / core count
- Place in the existing `sys-cpu` panel below the aggregate line, or as a dedicated row
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## Acceptance Criteria
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- [ ] #1 Per-core CPU percentages shown as labeled bars
- [ ] #2 Bars are color-coded by utilization level
- [ ] #3 Layout adapts to core count (wraps to multiple rows)
- [ ] #4 Updates on same SYS_REFRESH_SECS interval as existing system stats
- [ ] #5 Fits within sys-cpu panel without requiring scroll on standard terminal widths
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