[ https://issues.apache.org/jira/browse/KUDU-2931?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Alexey Serbin updated KUDU-2931: -------------------------------- Description: It seems the following code might lead to calling {{KuduScanner.nextRows()}} again after it has returned {{null}} already in case if the underlying scanner had expired and closed by the tablet server serving the request: https://github.com/apache/kudu/blob/737930f3cd0c0caba3c36944f91058ffaead4714/java/kudu-spark/src/main/scala/org/apache/kudu/spark/kudu/KuduRDD.scala#L88-L91 However, calling {{Kudu.nextRows()}} after it returned {{null}} might lead to undefined behavior: https://github.com/apache/kudu/blob/737930f3cd0c0caba3c36944f91058ffaead4714/java/kudu-client/src/main/java/org/apache/kudu/client/KuduScanner.java#L48-L59 Starting Kudu 1.8, the auto-keepalive provision makes the described issue less likely to manifest itself: https://github.com/apache/kudu/commit/cf1b1f42cbcc3ee67477ddc44cd0ff5070f1caac was: It seems the following code might lead to calling {{KuduScanner.nextRows()}} again after it has returned {{null}} already in case of the underlying scanner had expired and closed by tablet server serving the request: https://github.com/apache/kudu/blob/737930f3cd0c0caba3c36944f91058ffaead4714/java/kudu-spark/src/main/scala/org/apache/kudu/spark/kudu/KuduRDD.scala#L88-L91 However, calling {{Kudu.nextRows()}} after it returned {{null}} might lead to undefined behavior: https://github.com/apache/kudu/blob/737930f3cd0c0caba3c36944f91058ffaead4714/java/kudu-client/src/main/java/org/apache/kudu/client/KuduScanner.java#L48-L59 Starting Kudu 1.8, the auto-keepalive provision makes the described issue less likely to manifest itself: https://github.com/apache/kudu/commit/cf1b1f42cbcc3ee67477ddc44cd0ff5070f1caac > RowIterator.hasNext might hang in certain scenarios > --------------------------------------------------- > > Key: KUDU-2931 > URL: https://issues.apache.org/jira/browse/KUDU-2931 > Project: Kudu > Issue Type: Bug > Components: client, java, spark > Affects Versions: 1.3.0, 1.3.1, 1.4.0, 1.5.0, 1.6.0, 1.7.0, 1.7.1 > Reporter: Alexey Serbin > Priority: Major > > It seems the following code might lead to calling {{KuduScanner.nextRows()}} > again after it has returned {{null}} already in case if the underlying > scanner had expired and closed by the tablet server serving the request: > > https://github.com/apache/kudu/blob/737930f3cd0c0caba3c36944f91058ffaead4714/java/kudu-spark/src/main/scala/org/apache/kudu/spark/kudu/KuduRDD.scala#L88-L91 > However, calling {{Kudu.nextRows()}} after it returned {{null}} might lead to > undefined behavior: > > https://github.com/apache/kudu/blob/737930f3cd0c0caba3c36944f91058ffaead4714/java/kudu-client/src/main/java/org/apache/kudu/client/KuduScanner.java#L48-L59 > Starting Kudu 1.8, the auto-keepalive provision makes the described issue > less likely to manifest itself: > > https://github.com/apache/kudu/commit/cf1b1f42cbcc3ee67477ddc44cd0ff5070f1caac -- This message was sent by Atlassian Jira (v8.3.2#803003)