[SERVER-74532] Journal flusher's persistent session causes WT to log warning Created: 02/Mar/23  Updated: 29/Oct/23  Resolved: 19/May/23

Status: Closed
Project: Core Server
Component/s: None
Affects Version/s: None
Fix Version/s: 7.0.0-rc2

Type: Bug Priority: Major - P3
Reporter: Louis Williams Assignee: Dianna Hohensee (Inactive)
Resolution: Fixed Votes: 0
Labels: None
Remaining Estimate: Not Specified
Time Spent: Not Specified
Original Estimate: Not Specified

Assigned Teams:
Storage Execution
Backwards Compatibility: Fully Compatible
Operating System: ALL
Sprint: Execution Team 2023-05-15, Execution Team 2023-05-29
Participants:

 Description   

Running the server for an hour, when idle, will log the following warning:

{"t":{"$date":"2023-03-01T10:53:37.015+00:00"},"s":"W",  "c":"WT",       "id":22430,   "ctx":"thread29","msg":"WiredTiger message","attr":{"message":{"ts_sec":1677668017,"ts_usec":15090,"thread":"5836:0x7fa4acd38700","session_name":"sweep-server","category":"WT_VERB_DEFAULT","category_id":9,"verbose_level":"WARNING","verbose_level_id":-2,"msg":"Session 13 (@: 0x0x55f142d9fae8 name: EMPTY) did not run a sweep for 60 minutes."}}}

With some GDB investigation, I discovered that this is the always-active session we use to flush the journal , and it is never reset for the lifetime of the server. As is noted in SERVER-31912, this does not cause problems because we never open cursors using this session.

WT-10675 proposes adding an API to set the "name" field that is currently EMPTY, but I'm not sure how we would use that in MongoDB to suppress this warning.



 Comments   
Comment by Githook User [ 19/May/23 ]

Author:

{'name': 'Dianna Hohensee', 'email': 'dianna.hohensee@mongodb.com', 'username': 'DiannaHohensee'}

Message: SERVER-74532 Periodically reset the WT_SESSION held for waitUntilDurable calls, so WT does not log about it
Branch: master
https://github.com/mongodb/mongo/commit/81ab74630f92a2076f5918198ae3175402f4b943

Comment by Donald Anderson [ 02/Mar/23 ]

If this thread could periodically call WT_SESSION.reset, that should solve the problem.  That method releases resources and runs any session sweeps that are needed.

Generated at Thu Feb 08 06:27:43 UTC 2024 using Jira 9.7.1#970001-sha1:2222b88b221c4928ef0de3161136cc90c8356a66.