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Failure Lab · Expert
Out-of-order FIFO
A FIFO queue is processing messages out of order despite being… FIFO. Customer 'A' sees their 'shipped' event before their 'paid' event.
Symptom · Messages within a logical group appear out of order in the consumer log.
Goal: Zero out-of-order pairs across 30 ticks.
Hint: Switch grouping strategy to per-customer.
order-eventsorders.fifo · t0Consumers
order-events
every 900ms
orders.fifo
0Visible0
In-flight0
fulfillment-1
idle
fulfillment-2
idle
Knobs
0
Pending
0
In-flight
0
Delivered
0
Out-of-order
0
Avg wait
0.0t
Avg rc
0.00
Empty polls
0
DLQ
0