Prefetch (QoS) ograničava koliko nepotvrženih poruka konzument može držati odjednom — kontrolirajući distribuciju rada i sprječavajući da jedan konzument bude preopterećen dok su drugi neaktivni. Važno je za pravičnu i učinkovitu obradu poruka.
Što prefetch radi
PREFETCH (QoS - prefetch count) → limits the number of UNACKNOWLEDGED messages a consumer
can have at once:
→ without it → RabbitMQ may dispatch many messages to one consumer (it grabs a batch)
→ with prefetch=N → a consumer gets at most N unacked messages at a time (must ack to get more)
→ controls how messages are distributed and how much a consumer buffers
