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Steve Loughran commented on HADOOP-16049: ----------------------------------------- # the fact that hasn't been picked up highlights some big failures in tests, *everywhere* # do you fancy taking up the backport problem? > DistCp result has data and checksum mismatch when blocks per chunk > 0 > ---------------------------------------------------------------------- > > Key: HADOOP-16049 > URL: https://issues.apache.org/jira/browse/HADOOP-16049 > Project: Hadoop Common > Issue Type: Bug > Components: tools/distcp > Affects Versions: 2.9.2 > Reporter: Kai Xie > Priority: Major > > In 2.9.2 RetriableFileCopyCommand.copyBytes, > {code:java} > int bytesRead = readBytes(inStream, buf, sourceOffset); > while (bytesRead >= 0) { > ... > if (action == FileAction.APPEND) { > sourceOffset += bytesRead; > } > ... // write to dst > bytesRead = readBytes(inStream, buf, sourceOffset); > }{code} > it does a positioned read but the position (`sourceOffset` here) is never > updated when blocks per chunk is set to > 0 (which always disables append > action). So for chunk with offset != 0, it will keep copying the first few > bytes again and again, causing result to have data & checksum mismatch. > To re-produce this issue, in branch-2, update BLOCK_SIZE to 10240 (> default > copy buffer size) in class TestDistCpSystem and run it. > HADOOP-15292 has resolved the issue reported in this ticket in > trunk/branch-3.1/branch-3.2 by not using the positioned read, but has not > been backported to branch-2 yet > > -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-issues-h...@hadoop.apache.org