jon-wei commented on a change in pull request #7425: Add is_overshadowed column to sys.segments table URL: https://github.com/apache/incubator-druid/pull/7425#discussion_r276808390
########## File path: core/src/main/java/org/apache/druid/timeline/SegmentWithOvershadowedStatus.java ########## @@ -0,0 +1,89 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ + +package org.apache.druid.timeline; + +import com.fasterxml.jackson.annotation.JsonCreator; +import com.fasterxml.jackson.annotation.JsonProperty; + +/** + * DataSegment object plus the overshadowed status for the segment. An immutable object. + * + * SegmentWithOvershadowedStatus's {@link #compareTo} method considers only the {@link SegmentId} of the DataSegment object. + */ +public class SegmentWithOvershadowedStatus implements Comparable<SegmentWithOvershadowedStatus> Review comment: > If I deconstruct the DataSegment object, then we might save few bytes on a reference to DataSegment, but then the memory savings in broker where interned DataSegment is used would be lost. With a flat representation in the wire format, you could still extract->create a DataSegment object and intern that. That said, given that there's a plan to move to smile format, I would lean towards keeping the existing SegmentWithOvershadowedStatus with the separate DataSegment field, since I like that structure better. With smile, the extra reference would only add an extra dictionary-encoded key and two braces, I believe, so the byte savings would be minimal and dwarfed by things like the column name list. I think this area is good enough for the goals of this PR, and we can always adjust this area later if needed as part of resolving the interning discussion in #7395 ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
