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Lars Hofhansl commented on HBASE-6900: -------------------------------------- [~ram_krish] Sorry for the delay. {code} {+ if (!checkReseek() && heap != null) {} {code} Do we need to call checkReseek here? This is a somewhat expensive operation and we're now doing it for every reseek issued to a StoreScanner. Could we just check for {{heap == null}} in the beginning of the method and return {{false}} if so? > RegionScanner.reseek() creates NPE when a flush or compaction happens before > the reseek. > ---------------------------------------------------------------------------------------- > > Key: HBASE-6900 > URL: https://issues.apache.org/jira/browse/HBASE-6900 > Project: HBase > Issue Type: Bug > Reporter: ramkrishna.s.vasudevan > Assignee: ramkrishna.s.vasudevan > Attachments: HBASE-6900_1.patch, HBASE-6900.patch > > > HBASE-5520 introduced reseek() on the RegionScanner. > Now when a scanner is created we have the StoreScanner heap. After this if a > flush or compaction happens parallely all the StoreScannerObservers are > cleared so that whenever a new next() call happens we tend to recreate the > scanner based on the latest store files. > The reseek() in StoreScanner expects the heap not to be null because always > reseek would be called from next() > {code} > public synchronized boolean reseek(KeyValue kv) throws IOException { > //Heap cannot be null, because this is only called from next() which > //guarantees that heap will never be null before this call. > if (explicitColumnQuery && lazySeekEnabledGlobally) { > return heap.requestSeek(kv, true, useRowColBloom); > } else { > return heap.reseek(kv); > } > } > {code} > Now when we call RegionScanner.reseek() directly using CPs we tend to get a > NPE. In our case it happened when a major compaction was going on. I will > also attach a testcase to show the problem. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira