Altinity / Altinity/clickhouse-operator

Large Cluster Configmap Limits

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planned for review research required
Dominant language
Go
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Avg merge
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Merged PRs (30d)
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Description

Hi All,
I recently hit an issue where I was trying to provision a large Clickhouse cluster (1000 shards) and hit a limit on the amount of nodes that could exist in the relevant configmap. After 807 nodes are provisioned the configmap is larger than 1MB in size which is a hard limit in K8S/etcd. I am wondering if there is a workaround or ideas on how to partition the config maps appropriately to work around this issue.

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Research direction

Start by examining how the operator stores ClickHouse cluster node data in Kubernetes ConfigMaps. Reproduce the reported limit with a large cluster and investigate partitioning the ConfigMaps so they remain below Kubernetes' 1 MB limit. Done means a 1000-shard cluster can be provisioned without exceeding the ConfigMap or etcd size limit.

Written by the indexing model from the issue text.

Assessment

Tech stack
clickhouse, go, kubernetes
Domain
databases, infrastructure
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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