[SERVER-20185] Scaling issue at high connection count with journal enabled under WiredTiger Created: 28/Aug/15 Updated: 11/Jan/16 Resolved: 16/Sep/15 |
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| Status: | Closed |
| Project: | Core Server |
| Component/s: | WiredTiger |
| Affects Version/s: | 3.0.6, 3.1.7 |
| Fix Version/s: | 3.1.8 |
| Type: | Bug | Priority: | Major - P3 |
| Reporter: | Bruce Lucas (Inactive) | Assignee: | Susan LoVerso |
| Resolution: | Done | Votes: | 0 |
| Labels: | None | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Attachments: |
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| Backwards Compatibility: | Fully Compatible | ||||||||||||||||
| Operating System: | ALL | ||||||||||||||||
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| Description |
Repro code:
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| Comments |
| Comment by Michael Cahill (Inactive) [ 16/Sep/15 ] |
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boylook this is one of the substantial changes in WiredTiger for MongoDB 3.2. There are no plans to backport it to 3.0: there are many code changes involved and they would likely destabilize the 3.0 branch. |
| Comment by hongyu.bi [ 16/Sep/15 ] |
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hi , if 3.0.x will get backport? cause we're using 3.0.6 on production |
| Comment by Daniel Pasette (Inactive) [ 16/Sep/15 ] |
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Closing as fixed. Any additional issues should be raised as separate issues. |
| Comment by Bruce Lucas (Inactive) [ 15/Sep/15 ] |
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I ran against a build I did this morning from MongoDB master, so not WT develop branch, nor --enable-diagnostic. I didn't encounter any functional problems, but this was just a performance test. |
| Comment by Susan LoVerso [ 15/Sep/15 ] |
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Thanks Bruce! What did you run with? The drop last week had a few bugs in it that are fixed. Are you running against our develop branch? Also are you running with --enable-diagnostic? I have some "force less common code path" for unbuffered writes in there in diagnostic mode. |
| Comment by Bruce Lucas (Inactive) [ 15/Sep/15 ] |
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New journal algorithm shows huge improvement, with nearly perfect scaling up to 10k connections. Thanks sue.loverso! Above 10k connections there is some negative scaling, but performance with journal remains close to performance without journal, so from my perspective it appears the new journal algorithm fixes this issue. I'll spin off a separate ticket to investigate the negative scaling not related to the journal.
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| Comment by Michael Cahill (Inactive) [ 11/Sep/15 ] |
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sue.loverso, can you please try this workload with MongoDB 3.1.8 (once your changes for |
| Comment by Daniel Pasette (Inactive) [ 28/Aug/15 ] |
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Parking with Bruce until |