[DOCS-10789] Docs for SERVER-19605: Oplog timeout should be configurable Created: 14/Sep/17 Updated: 29/Oct/23 Resolved: 14/Nov/17 |
|
| Status: | Closed |
| Project: | Documentation |
| Component/s: | None |
| Affects Version/s: | None |
| Fix Version/s: | 3.5.14, 3.6.0-rc0, 3.4.11 |
| Type: | Task | Priority: | Major - P3 |
| Reporter: | Kay Kim (Inactive) | Assignee: | Andrew Aldridge |
| Resolution: | Fixed | Votes: | 0 |
| Labels: | neweng | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Issue Links: |
|
||||||||
| Participants: | |||||||||
| Days since reply: | 6 years, 13 weeks, 1 day ago | ||||||||
| Epic Link: | DOCS: 3.6 Server | ||||||||
| Story Points: | 0.5 | ||||||||
| Description |
Documentation Request Summary:I added a new server parameter, 'oplogInitialFindMaxSeconds' which configures how long the initial `find` command on the oplog waits before it times out. Engineering Ticket Description:Issue Status as of March 1, 2017 We intend to provide this functionality the during 3.5 development cycle and will evaluate the feasibility of backporting to MongoDB 3.4. Please be aware this log message is typically symptomatic of an overloaded primary. Therefore, while increasing the oplog timeout may prevent these messages from being logged, it would likely not resolve the replication lag that is being observed. For MongoDB-related support discussion, I would recommend posting on the mongodb-user group or Stack Overflow with the mongodb tag. A question about how to resolve replication lag involves more discussion would be best posted on the mongodb-users group. Original descriptionWe just encountered a situation where all secondaries in two of our replica sets had ceased replication, and were 1-2 days behind the primary. This appears to have been caused in part by the fact that the initial oplog query from SECONDARY->PRIMARY times out after 30 seconds, but the oplog query takes > 5 minutes to run. Some searching led me to this JIRA As a workaround, we are building a custom binary with an increased oplog timeout so that the initial oplog query is allowed to complete and so our secondaries have a chance to catch up. Ideally, this value would be configurable with a flag or configuration option to avoid the need to recompile, and to allow users to customize the timeout for their particular situation. We have a fairly large oplog:
Here are some sample queries issued by the secondaries that are timing out:
|
| Comments |
| Comment by Githook User [ 14/Nov/17 ] |
|
Author: {'name': 'Andrew Aldridge', 'username': 'i80and', 'email': 'i80and@foxquill.com'}Message: |