KAFKA-7779: Avoid unnecessary loop iteration in leastLoadedNode #6081
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https://issues.apache.org/jira/browse/KAFKA-7779 In NetworkClient.leastLoadedNode, it invokes `isReady` to check if an established connection exists for the given node. `isReady` checks whether metadata needs to be updated also which wants to make metadata request first priority. However, if the to-be-sent request is metadata request, then we do not have to check this otherwise the loop in `leastLoadedNode` will do a complete iteration until the final node is selected. That's not performance efficient for a large cluster.
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retest this please |
hachikuji
reviewed
Jan 5, 2019
| @@ -652,7 +652,8 @@ public Node leastLoadedNode(long now) { | |||
| int idx = (offset + i) % nodes.size(); | |||
| Node node = nodes.get(idx); | |||
| int currInflight = this.inFlightRequests.count(node.idString()); | |||
| if (currInflight == 0 && isReady(node, now)) { | |||
| if (currInflight == 0 && | |||
| (this.metadataUpdater.isUpdateDue(now) ? canSendRequest(node.idString(), now) : isReady(node, now))) { | |||
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I think we may be able to simplify this and just use canSendRequest. If a metadata update is due (which is a rare case), we will still be prevented from sending. It doesn't seem like we get any benefit from having leastLoadedNode choose a different node which may have in-flight requests.
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retest this please |
1 similar comment
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retest this please |
dhruvilshah3
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Apr 29, 2019
* ak/trunk: (42 commits) KAFKA-8134: `linger.ms` must be a long KAFKA-7779; Avoid unnecessary loop iteration in leastLoadedNode (apache#6081) MINOR: Update Gradle to 5.4.1 and update its plugins (apache#6436) MINOR: improve Session expiration notice (apache#6618) KAFKA-8029: In memory session store (apache#6525) MINOR: In-memory stores cleanup (apache#6595) KAFKA-7862 & KIP-345 part-one: Add static membership logic to JoinGroup protocol (apache#6177) KAFKA-8254: Pass Changelog as Topic in Suppress Serdes (apache#6602) KAFKA-7903: automatically generate OffsetCommitRequest (apache#6583) KAFKA-8291 : System test fix (apache#6637) MINOR: Do not log retriable offset commit exceptions as errors (apache#5904) MINOR: Fix log message error of loadTransactionMetadata (apache#6571) MINOR: Fix 404 security features links (apache#6634) MINOR: Remove an unnecessary character from broker's startup log MINOR: Make LogCleaner.shouldRetainRecord more readable (apache#6590) MINOR: Remove implicit return statement (apache#6629) KAFKA-8237; Untangle TopicDeleteManager and add test cases (apache#6588) KAFKA-8227 DOCS Fixed missing links duality of streams tables (apache#6625) MINOR: reformat settings.gradle to be more readable (apache#6621) MINOR: Correct RestServerTest formatting ... Conflicts: build.gradle settings.gradle
pengxiaolong
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Jun 14, 2019
…he#6081) In NetworkClient.leastLoadedNode, we invoke `isReady` to check if an established connection exists for the given node. `isReady` checks whether metadata needs to be updated also which wants to make metadata request first priority. However, if the to-be-sent request is metadata request, then we do not have to check this otherwise the loop in `leastLoadedNode` will do a complete iteration until the final node is selected. Reviewers: Jason Gustafson <jason@confluent.io>
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https://issues.apache.org/jira/browse/KAFKA-7779
In NetworkClient.leastLoadedNode, it invokes
isReadyto check if an established connection exists for the given node.isReadychecks whether metadata needs to be updated also which wants to make metadata request first priority. However, if the to-be-sent request is metadata request, then we do not have to check this otherwise the loop inleastLoadedNodewill do a complete iteration until the final node is selected. That's not performance efficient for a large cluster.More detailed description of your change,
if necessary. The PR title and PR message become
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