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Signal Path: How the routing layer actually decides, for engineers evaluating the runtime

Signal Path See the approach

Signal Path

engineers evaluating the runtime

How the routing layer actually decides

See the approach

Four parts

  1. Placement model
  2. Preemption ladder
  3. Backpressure
  4. Failure domains
HEIGHT · PRIORITY01020304

Parts

What each Signal Path part does

  1. 01

    Placement model

    The real cost function, including the fairness constraint most schedulers leave out.

  2. 02

    Preemption ladder

    What gets evicted first, and which guarantees survive an eviction.

  3. 03

    Backpressure

    How queue depth turns into admission decisions upstream of the scheduler.

  4. 04

    Failure domains

    Spread rules, and what they cost you in packing efficiency.

Priorities

Which Signal Path parts to read first.

  1. 01

    Core

    Two parts: placement model and preemption ladder.

  2. 02

    Supporting

    Two parts: backpressure and failure domains.

Before you ask

Questions about Signal Path.

Who is Signal Path written for?

Engineers evaluating the runtime.

What does Signal Path not cover?

Anything that is not one of its four parts.

Next step

Start with placement model.

Three more parts follow in the index above.

See the approach Read all four parts