[SERVER-79805] Explain command does not report executionStats on mongos Created: 07/Aug/23 Updated: 17/Aug/23 |
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| Status: | Backlog |
| Project: | Core Server |
| Component/s: | None |
| Affects Version/s: | None |
| Fix Version/s: | None |
| Type: | Improvement | Priority: | Major - P3 |
| Reporter: | Arun Banala | Assignee: | Backlog - Query Execution |
| Resolution: | Unresolved | Votes: | 0 |
| Labels: | query-product-scope-2, query-product-urgency-3, query-product-value-3 | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Assigned Teams: |
Query Execution
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| Participants: |
| Description |
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I've noticed that for sharded collections, we report executionStats under the shards field for each sub-pipeline that gets executed on the individual shards. But we don't have any information about what is happening on mongos during the $mergeCursors or the stages after the $mergeCursors. For example, a $group or a $sort could spend a significant amount of time after the $mergeCursors and we provide no information about that in the explain. There could also be a network latency between the mongos and mongod communication that would be easy to identify if we report executionStats on mongos. |
| Comments |
| Comment by Xiaochen Wu [ 17/Aug/23 ] |
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product triage: We haven't heard any customer asking for this. And since we are introducing a new explain for CQF, we'd defer this effort to future improvements. Sending it to backlog. |
| Comment by Ana Meza [ 14/Aug/23 ] |
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Passing to product to decide on priority |