Details
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Bug
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Resolution: Cannot Reproduce
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Major
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6.5.0
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uname -a
Linux couch01 4.19.0-6-amd64 #1 SMP Debian 4.19.67-2+deb10u1 (2019-09-20) x86_64 GNU/Linux
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Untriaged
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Unknown
Description
First I understand that vBuckets != 1024 is not supported (but we do have 64 vBuckets for macOS).
When exploring Eventing performance characteristics on a non-MDS one node server ( e.g. why is it slow on a single Linux node) at various vBuckets settings 1024, 512, 256, 128 and 64 - these all worked.
SELECT count cnt, type from `travel-sample` group by type |
1968 airport
917 hotel
4495 landmark
24024 route
187 airline
I then tried 340 (which is not a factor of 1024) to emulate a 3 node KV system my eventing test worked as expected BUT N1QL queries did not.
1024/340 = 3.0117
We get wrong answers via N1QL if COUCHBASE_NUM_VBUCKETS is set to a non factor of 1024:
export COUCHBASE_NUM_VBUCKETS=340
install couchbase and setup then load `travel-sample` run these two queries
SELECT count cnt from `travel-sample` |
cnt
31591
SELECT count cnt, type from `travel-sample` group by type |
4 airline
18 airport
8 hotel
56 landmark
312 route
SELECT count cnt from `travel-sample` where type = 'hotel' |
cnt
917