[SERVER-34460] Mongos will not pick up database versions for database entries it already has cached after setFCV 4.0 Created: 13/Apr/18  Updated: 13/Apr/18  Resolved: 13/Apr/18

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

Type: Bug Priority: Major - P3
Reporter: Esha Maharishi (Inactive) Assignee: Esha Maharishi (Inactive)
Resolution: Won't Fix Votes: 0
Labels: None
Remaining Estimate: Not Specified
Time Spent: Not Specified
Original Estimate: Not Specified

Issue Links:
Related
is related to SERVER-33783 Make shards and mongos do full routin... Closed
Operating System: ALL
Sprint: Sharding 2018-04-23
Participants:

 Description   

This is because mongos will only refresh an entry it has already cached if it is told the entry is stale.

However, it will only be told the entry is stale if it receives StaleDbVersion from some shard, which can only happen if it attaches a databaseVersion in the request to the shard (and of course, mongos won't attach a database version if its cache entry does not have a database version).



 Comments   
Comment by Esha Maharishi (Inactive) [ 13/Apr/18 ]

Closing as Won't Fix. We decided not to handle this in 4.0, since no new features in 4.0 depend on database versioning.

Database versioning will start working correctly in 4.2, because to upgrade to 4.2, the mongoses must be restarted as v4.2, which clears all of their in-memory state (including the cache of database entries).

(Note that 4.2 mongoses will always expect database entries to have database versions).

CC schwerin, kaloian.manassiev

Generated at Thu Feb 08 04:36:46 UTC 2024 using Jira 9.7.1#970001-sha1:2222b88b221c4928ef0de3161136cc90c8356a66.