Hi, I am trying to calculate 95th percentile. Have add the below metricsSpec to the ingestion spec. "metricsSpec": [ { "name": "quantiles_doubles_Search Response Latency", "type": "quantilesDoublesSketchToQuantile", "fieldName": "Search Response Latency", "fraction": 0.95 } ] Got this error: Error: Please make sure to load all the necessary extensions and jars with type 'quantilesDoublesSketchToQuantile' on 'druid/coordinator' service. Could not resolve type id 'quantilesDoublesSketchToQuantile' as a subtype of

org.apache.druid.query.aggregation.AggregatorFactory

known type ids = [HLLSketchBuild, HLLSketchMerge, arrayOfDoublesSketch, cardinality, count, distinctCount, doubleAny, doubleFirst, doubleLast, doubleMax, doubleMean, doubleMin, doubleSum, expression, filtered, floatAny, floatFirst, floatLast, floatMax, floatMin, floatSum, grouping, histogram, hyperUnique, javascript, longAny, longFirst, longLast, longMax, longMin, longSum, passthrough, quantilesDoublesSketch, quantilesDoublesSketchMerge, sketchBuild, sketchMerge, stringAny, stringFirst, stringFirstFold, stringLast, stringLastFold, thetaSketch] (for POJO property 'metricsSpec') at [Source: (org.eclipse.jetty.server.HttpInputOverHTTP); line: 1, column: 30742] (through reference chain: org.apache.druid.indexing.overlord.sampler.IndexTaskSamplerSpec["spec"]->org.apache.druid.indexing.common.task.IndexTask$IndexIngestionSpec["dataSchema"]->org.apache.druid.segment.indexing.DataSchema["metricsSpec"]->java.lang.Object[][4]) This is the load list given in config: druid.extensions.loadList=["druid-hdfs-storage", "druid-kafka-indexing-service", "druid-datasketches", "druid-multi-stage-query", "druid-google-extensions", "prometheus-emitter", "druid-basic-security", "druid-distinctcount"] Can someone please help how to configure this correctly.

hi @Archana Sabbarapu. The error message in this case may be slightly misleading because you’re specifying a post aggregator

quantilesDoublesSketchToQuantile

and I do see

druid-datasketches

extension in the load list which houses all the sketch-related aggregators and post-aggregators. The error says that you can only have aggregators of those specific types (and no post-aggregators). Going back to your question, are you specifying the post aggregator during ingestion time or query time? I don’t think you can specify them at ingestion time. Also, are

name

and

fieldName

correct? (they seem to have spaces in them). Please see https://druid.apache.org/docs/latest/querying/post-aggregations.html on how to use post aggregators. Hope that helps