[SERVER-29285] ScopedCollectionMetadata compare equal Created: 18/May/17  Updated: 30/Oct/23  Resolved: 26/Sep/17

Status: Closed
Project: Core Server
Component/s: Sharding
Affects Version/s: None
Fix Version/s: 3.5.9

Type: Improvement Priority: Major - P3
Reporter: Nathan Myers Assignee: Nathan Myers
Resolution: Fixed Votes: 0
Labels: None
Remaining Estimate: Not Specified
Time Spent: Not Specified
Original Estimate: Not Specified

Backwards Compatibility: Fully Compatible
Participants:

 Description   

Killing specific queries that depend on a range that a secondary has been notified is being deleted requires (1) identifying CollectionMetadata instances that have a chunk overlapping it, and (2) invalidating queries that have a ScopedCollectionMetadata that refers to one such instance. For (2), it suffices to provide op== / op!= on ScopedCollectionMetadata.

Assumption is that most running queries on a collection will seem to depend on any given chunk being removed, and the majority of those will be expected to die, so a scan of all such running queries for each such event is more economical than keeping a list of queries that depend on each CollectionMetadata.



 Comments   
Comment by Nathan Myers [ 26/Sep/17 ]

Implemented in 20e9320f7716515d68c27324dc20080d585fd70f
"SERVER-29342 CollectionShardState/RangeDeleter support for safe secondary reads"
nathan.myers 2017-06-02 13:16:12

Comment by Kaloian Manassiev [ 14/Sep/17 ]

nathan.myers, can you check whether this is still necessary or already done?

Generated at Thu Feb 08 04:20:24 UTC 2024 using Jira 9.7.1#970001-sha1:2222b88b221c4928ef0de3161136cc90c8356a66.