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Confidence Based Dynamic Migration

A fluid queue (or stochastic fluid model) is a mathematical model used to describe the fluid level in a reservoir subject to randomly determined periods of filling and emptying. »Fluid Queuing Model

As the system grows

When can we move from Event Driven to Fluid simulation ? and

when can we move from Fluid Simulation to Analytic Models.

Fluid models modulated by discrete (or Markovian) models are commonly used.

We can dynamically study the metrics being computed from a detailed simulation.

We can then parameterise a simple estimator based on these measurements and use that in place of the detailed simulation.

Occasionally we re-enable the detailed simulation and check it is giving the same metrics as before (i.e. the metrics are stationary) and also check its output versus the detailed results running shotgun. On discrepancy, abort, rollback or just recalibrate, depending on severity.

Hamming distance on busses: TLM POWER3 does this on the generic payload fields.


7: (C) 2012-16, DJ Greaves, University of Cambridge, Computer Laboratory.