[SERVER-68642] Create new config.placementHistory collection as part of the config server startup routine Created: 08/Aug/22  Updated: 29/Oct/23  Resolved: 18/Aug/22

Status: Closed
Project: Core Server
Component/s: None
Affects Version/s: None
Fix Version/s: 6.1.0-rc0

Type: Task Priority: Major - P3
Reporter: Paolo Polato Assignee: Paolo Polato
Resolution: Fixed Votes: 0
Labels: None
Remaining Estimate: Not Specified
Time Spent: Not Specified
Original Estimate: Not Specified

Backwards Compatibility: Fully Compatible
Sprint: Sharding EMEA 2022-08-22
Participants:

 Description   

In order to optimise the connections opened by a mongos process when a nss.watch() request is received, the config server will have to persist in a new collection (called config.placementHistory) historical metadata about which shards of the cluster were hosting one or more chunks of nss at a specific point in time.

The objectives of this ticket are:

  • The encoding of the schema for config.placementHistory, defined as

    {
    namespace: string, // references db or collection
    timestamp: Timestamp,
    shards: array<ShardId> // may be empty
    }
    

  • The instantiation of config.placementHistory as part of the initialisation of the ShardingCatalogManager (with an index over namespace+timestamp).


 Comments   
Comment by Githook User [ 18/Aug/22 ]

Author:

{'name': 'Paolo Polato', 'email': 'paolo.polato@mongodb.com', 'username': 'ppolato'}

Message: SERVER-68642 add config.placementHistory collection to sharding catalog
Branch: master
https://github.com/mongodb/mongo/commit/4a21dc8db7343c74ea17c30df2911601ed430e12

Generated at Thu Feb 08 06:11:21 UTC 2024 using Jira 9.7.1#970001-sha1:2222b88b221c4928ef0de3161136cc90c8356a66.