yugabyte/yugabyte-db

[read-replicas] spurious logging (?): Expected replicas 3 but found 11 for tablet

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#3,235 opened on Dec 31, 2019

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Description

Jira Link: DB-1673 On a cluster with 3 primary replicas, and 8 read replicas, user reported the following:

The master's started logging a lot of Expected replicas 3 but found 11 for tablet halfway into the spike in errors.

The log line seems misleading (since 11 is indeed the expected number of replicas for the tablet in this setup).

Can we look to see if it is just spurious logging or a logic issue in master interpreting the read-replicas incorrectly?

Contributor guide

Research direction
Investigate the master's logging logic for 'Expected replicas X but found Y'. Check if the count includes read replicas. Determine if the log is spurious or indicates a bug in replica count calculation.
Tech stack
ccpp
Domain
databasesdistributed systems
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
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.
Needs investigation
Prerequisites
distributed systems knowledge
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
30