[SERVER-21230] Insert performance degrades drastically or hangs on large capped collection with WiredTiger Created: 30/Oct/15 Updated: 07/Apr/23 Resolved: 24/Nov/15 |
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| Status: | Closed |
| Project: | Core Server |
| Component/s: | WiredTiger |
| Affects Version/s: | 3.0.1, 3.0.6 |
| Fix Version/s: | None |
| Type: | Bug | Priority: | Major - P3 |
| Reporter: | Denys | Assignee: | Unassigned |
| Resolution: | Incomplete | Votes: | 0 |
| Labels: | needs-repo | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Attachments: |
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| Operating System: | Linux | ||||
| Participants: | |||||
| Description |
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We are using MongoDB to store some historical data and occasionally insert performance degrades drastically (up to hour for one record) or hangs.
pstack, WiredTiger stats, parts of mongod log, biggest DB stats and few longest Operations are attached. |
| Comments |
| Comment by Denys [ 01/Dec/15 ] |
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Hi Ramon Issue is reproduced again on 3.0.7 enterprise. Will try to reach our db team to open commercial support ticket. Can I collect some additional useful data from instance while it hanging? I can left it for few days in this state. |
| Comment by Ramon Fernandez Marina [ 24/Nov/15 ] |
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Thanks for the update s.dixenon@gmail.com. I'm going to close this ticket for now, but if you see this behavior again please post here so we can reopen of just open a new ticket. Regards, |
| Comment by Denys [ 24/Nov/15 ] |
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Unfortunately I was able to upgrade only few days ago so it's too short period to have any results. |
| Comment by Ramon Fernandez Marina [ 23/Nov/15 ] |
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s.dixenon@gmail.com, is this still an issue for you? Have you observed the same behavior in 3.0.7? Thanks, |
| Comment by Ramon Fernandez Marina [ 31/Oct/15 ] |
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s.dixenon@gmail.com, I believe you're experience some performance-related issues with deletions on capped collections in earlier 3.0 versions that have been addressed in 3.0.7: I am trying to reproduce this ticket locally in case this ticket uncovers a new bug related to capped collections, but I'd recommend you upgrade to 3.0.7 to get better performance out of capped collections. |
| Comment by Denys [ 30/Oct/15 ] |
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Thanks for quick answer. Forget to mention that database contains single capped collection, current stats attached. Typical usage scenario – about 10M inserts and few hundred indexed queries for few hours during the day. |
| Comment by Ramon Fernandez Marina [ 30/Oct/15 ] |
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Thanks for the detailed report. The only thing that seems odd in the WT stats is reconciliation numbers, I've uploaded a visual representation of it. Looking at the logs I see the slow inserts on the testHarnessSIT_N database; given its size it may take a while to reproduce this behavior onsite. Can you please provide some more information about this deployment? What's the machine size, available memory, etc.? Thanks, |