Hi,
I’ve been noticing higher CPU usage in query service, so I started investigating. Only thing I noticed is that I see a lot of backfill file logs from query.log.
I checked “scan-cap” value according to https://developer.couchbase.com/documentation/server/current/settings/query-settings.html and confirmed that it is set to 0 (disabled).
Is it expected to see scan backfill activities when scan-cap is set to 0 ?
Is there a way to find out which query is getting backfilled? I’ve made sure that my query results are within reasonable size.
Thanks!
vsr1
July 12, 2018, 2:40am
2
scan-cap <=0 makes it default value 512. DOC-3795
Set high value. cc @deepkaran.salooja is there any way disable backfill from indexer side.
In 5.5 https://developer.couchbase.com/documentation/server/5.5/settings/cluster-settings.html
Check system:completed_requests for high PhaseCounts for IndexScan
1 Like
Thank you so much. I had no idea CB 4.5 had such features. That’s really nice to have
vsr1
July 12, 2018, 12:06pm
4
scan_cap is only 5.0 feature
Oh no…I meant those monitoring features. I thought those were new to 5. I did not know they were in 4.5.
vsr1
July 12, 2018, 6:44pm
6
In 4.5 monitoring is through queries. In 5.0 Enhanced monitoring, added profiling are integrated with Query Workbench. cc @marcoeg
https://blog.couchbase.com/optimize-n1ql-performance-using-request-profiling/
In 5.0, backfill can be disabled by setting “queryport.client.settings.backfillLimit” to 0 using the indexer setting url.
