Infrastructure · Primitives

Warmup

Gradual capacity increase to stabilize cold systems

Definition

Mechanism

On activation, accept load at `initial_capacity` and raise the accepted-load cap to full over `ramp_duration`, following `curve`. This prevents a thundering herd against a cold system. What the ramp establishes is the cap, not readiness — a system whose cap has reached full may still be cold inside. Utilizes Greet, Throttle.

Preconditions

  1. System state is inactive or reset

Postconditions

  1. Accepted-load cap has reached full capacity
  2. System is accepting load at full cap — readiness of internal state (caches, compiled paths) is a separate signal this pattern does not assert

Invariants

  1. Capacity Limit: Accepted_Load <= Current_Warmup_Cap(t)

Risks

Failure modes

  1. Premature Load

    Traffic arrives before warmup completes.

  2. False Warmth

    Timer completes but internal state (e.g. cache) is still cold.

Relationships

Builds on

References

Greet

Agent connection initiation

System

Complex whole of interacting parts

Throttle

Rate-limiting to prevent resource exhaustion

Used by

References

Reference

Parameters

curve Enum, {Linear, Exponential, Step}
Default: Linear
initial_capacity Float, [0.0, 1.0]
Starting capacity as fraction of full (0 = cold start)
ramp_duration Duration, [10s, 1h]
Time to reach full capacity from initial

Identity

Ref
Warmup#ed16
Sema ID
sema:Warmup#mh:SHA-256:ed16f499e655d6d252a2bae39a8cc87ec8497426107905501920ac47644be9ef
Ring
0
Tier
1
Updated
2026-11-11
Supersedes
  • sema:Warmup#mh:SHA-256:28c434be6a4de607158375965b76e4cb67d742481b6b6fb840326a7610703ceb
  • sema:Warmup#mh:SHA-256:7ad05d8c27bdabb565d72ce56d8a896af84e5c35d5bc56afb7bdecdac5b40551
  • sema:Warmup#mh:SHA-256:32d4b559fc99f4dfa7a154487385194fe1c4f5cd3589a5910d2ee35eadc38fff
  • sema:Warmup#mh:SHA-256:316ee053b8fda86e03974bb8baaf6c82b4de0b07ea7e55fa38d337309cfe25de