Is this only a ByteOrderPartitioner problem?
On Wed, Jan 29, 2014 at 7:34 PM, Tyler Hobbs <ty...@datastax.com> wrote: > Ignace, > > Thanks for reporting this. I've been able to reproduce the issue with a > unit test, so I opened > https://issues.apache.org/jira/browse/CASSANDRA-6638. I'm not 100% sure > if your fix is the correct one, but I should be able to get it fixed > quickly and figure out the full set of cases where a key (or keys) may be > skipped. > > > On Wed, Jan 29, 2014 at 9:53 AM, Desimpel, Ignace < > ignace.desim...@nuance.com> wrote: > >> Got into a problem when testing a vnode setup. >> >> I'm using a byteordered partitioner, linux, code version 2.0.4, >> replication factor 1, 4 machine >> >> All goes ok until I run cleanup, and gets worse when adding / >> decommissioning nodes. >> >> >> >> In my opinion the problem can be found in the SSTableScanner:: >> KeyScanningIterator::computeNext routine at the lines >> >> >> >> currentRange = rangeIterator.next(); >> >> seekToCurrentRangeStart(); >> >> if (ifile.isEOF())return endOfData(); >> >> >> >> To see what is wrong, think of having 3 ranges in the list, and both the >> first and second range will not produce a valid currentKey. The first time >> in the loop we get the first range, and then call >> seekToCurrentRangeStart(). That routine doesn't do anything in that case, >> so then the first key is read from the sstable. But this first key does not >> match the first range, so we loop again. We get the second range and call >> seekToCurrentRangeStart() again. Again this does not do anything, leaving >> all file pointers. So then a new currentKey is read from the sstable BUT >> that should not be the case. We should, in that case, continue to test with >> the 'old' currentKey. So in that case we are SKIPPING (possible) VALID >> RECORDS !!! >> >> >> >> To make things worse, in my test case, I only had one key. So when I get >> into the second loop, the test isEOF() was true, so the routine stopped >> immediately having 100 ranges still to test. >> >> >> >> Anyway, attached a new version of the SSTableScanner.java file. Seems to >> work for me, but I'm sure a more experienced eye should have a look at this >> problem (and/or possible other scanners and/or situations like scrub, range >> queries ...?). >> >> >> >> Well, I hope I'm wrong about this.... >> >> >> >> Regards, >> >> >> >> Ignace Desimpel >> >> >> >> >> >> >> >> >> > > > > -- > Tyler Hobbs > DataStax <http://datastax.com/> >
