Kefiw

Archived noindex page. Kefiw's public focus is Property decision help.

Archived page

This older Kefiw page is kept for reference, marked noindex, and removed from the primary sitemap. The current Kefiw experience is focused on property decisions: cost, quotes, damage, buying, selling, owning, and packets.

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Task Switching Tax · Context Overhead

CPU overhead of concurrent projects · 0.80^(n−1) retention curve.

Switching between contexts compounds. One task = 100%. Two = 80%. Three = 64%. By the fifth concurrent project, only 41% of your hours survive the overhead. This meter shows the CPU split between user process and system overhead.

Part of: Cognitive Throughput

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Fields marked optional can be skipped; results update as you type
Task Switching Tax · Context Overhead
CPU Usage · System Overhead
USER 51%
OVERHEAD 49%
Each additional task costs ~20% of remaining capacity · n=4
Effective Throughput
51.2%
Switching tax: 3.9 h of your day lost to The Gap
Usable hours
4.10 h
Burned in context-swap
3.90 h
Retention factor
0.8^3
Loss = 1 − 0.80^(n−1). Each additional concurrent context costs 20% of remaining capacity. Single-tasking (n=1) = 100%. At n=5, only 41% of your hours survive context-switching overhead.

How to use

  1. Enter number of distinct concurrent contexts (projects, clients, channels).
  2. Enter workday hours.
  3. Retention = 0.80^(n−1). Loss = 1 − retention. Multiply by workday hours.
  4. When OVERHEAD ≥ 45% you are running the OS, not the application.

Examples

n = 4 · 8h day
Retention 51.2% · Effective 4.1h · Switching tax 3.9h.
n = 2 · 8h day
Retention 80% · Effective 6.4h · Switching tax 1.6h.

Before you act on the result

Logic tools help expose a tradeoff, but they cannot see the full situation around the decision. Use the result to slow down the choice and name the assumption that matters most.

If one input drives the answer, test that assumption before treating the result as stable.

Next up

Fewer switches? Now measure your deep-work capacity.Deep Work Capacity · Focus Horizon → Context overhead has a hidden cost: willpower.Decision Fatigue · Willpower Battery →

Frequently asked questions

› Why 20% per task? Troubleshooting

Rough heuristic from Weinberg (1992) and reproduced in several attention-research reviews. Exact percentage is domain-dependent but the geometric-decay shape is consistent.

› Does batching help?

Massively. Consolidating 5 contexts into 2 time-boxed windows recovers ~40% of your day — which is why time-blocking works and Slack doesn't.

Tips & related reading

See the Cognitive Throughput hub →

Tips & how-tos

Relevant links

Related tools

Signal-to-Noise · Content Throughput

Measure how much of your daily information intake converts into actionable decisions. Throughput-pipe visual with clogged / flowing state.

Decision Fatigue · Willpower Battery

Model remaining willpower across the day. Every decision draws from the same finite reserve — trivial × 1, moderate × 5, heavy × 10.

Deep Work Capacity · Focus Horizon

Exponential decay model of focus quality. e^(−0.01×min) half-life ≈ 69 minutes — the horizon shows how long until quality drops below usable.