ARCHIVED from builddistributedsystem.com on 2026-04-28 — URL: https://builddistributedsystem.com/tracks/gossiper/tasks/task-3-4-batching
TASK

Implementation

Reduce network overhead by batching multiple messages into single transmissions. Instead of sending immediately, buffer messages and flush periodically or when the buffer reaches a threshold.

Sample Test Cases

Messages are batched togetherTimeout: 10000ms
Input
{"src":"c0","dest":"n1","body":{"type":"init","msg_id":1,"node_id":"n1","node_ids":["n1"]}}
{"src":"c0","dest":"n1","body":{"type":"topology","msg_id":2,"topology":{"n1":[]}}}
{"src":"c1","dest":"n1","body":{"type":"broadcast","msg_id":3,"message":1}}
{"src":"c2","dest":"n1","body":{"type":"broadcast","msg_id":4,"message":2}}
{"src":"c3","dest":"n1","body":{"type":"broadcast","msg_id":5,"message":3}}
{"src":"c4","dest":"n1","body":{"type":"read","msg_id":6}}
Expected Output
{"src":"n1","dest":"c0","body":{"type":"init_ok","in_reply_to":1,"msg_id":0}}
{"src":"n1","dest":"c0","body":{"type":"topology_ok","in_reply_to":2,"msg_id":1}}
{"src":"n1","dest":"c1","body":{"type":"broadcast_ok","in_reply_to":3,"msg_id":2}}
{"src":"n1","dest":"c2","body":{"type":"broadcast_ok","in_reply_to":4,"msg_id":3}}
{"src":"n1","dest":"c3","body":{"type":"broadcast_ok","in_reply_to":5,"msg_id":4}}
{"src":"n1","dest":"c4","body":{"type":"read_ok","in_reply_to":6,"msg_id":5,"messages":[1,2,3]}}

Hints

Hint 1▾
Buffer messages before sending
Hint 2▾
Use a time-based flush
Hint 3▾
Balance latency vs throughput
OVERVIEW

Theoretical Hub

Batching Trade-offs

Batching improves throughput by reducing per-message overhead but increases latency. The optimal batch size depends on message rate, network latency, and consistency requirements.

Key Concepts

batchingthroughput optimizationlatency tradeoff
main.py
python
Add Message Batching to Reduce Network Overhead - The Gossiper | Build Distributed Systems