envoyproxy/envoy

Change Redis cluster discovery to use CLUSTER_SHARDS API

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#36,975 opened on Nov 4, 2024

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area/redisenhancementhelp wanted

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Description

Title: Change Redis cluster discovery to use CLUSTER_SHARDS API

Description: Currently Envoy uses CLUSTER_SLOTS to fetch cluster topology from Redis. CLUSTER_SLOTS is deprecated in Redis 7.0. It is slower and less efficient than the new API, CLUSTER_SHARDS. We observed CLUSTER_SHARDS payload size to be 10x smaller than the CLUSTER_SLOTS payload for big redis cluster with 12k shards.

Redis doc also recommends using CLUSTER_SHARDS over CLUSTER_SLOTS

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Contributor guide

Research direction
Examine the current Redis cluster discovery using CLUSTER SLOTS in envoy/source/common/redis/. Understand how the cluster topology is fetched and parsed. Then implement the new CLUSTER SHARDS API, adapting the parsing logic. Update tests in envoy/test/common/redis/.
Tech stack
cppredis
Domain
backendinfrastructure
Issue type
Performance
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
C++Redis
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65