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Igor Vikhrov commented on HBASE-9582: ------------------------------------- Also I've noticed that problem is solved by setting "setCaching" to less value (for example,2). In this case same Scans give same results. > MapReduce Scan gives different output every times > ------------------------------------------------- > > Key: HBASE-9582 > URL: https://issues.apache.org/jira/browse/HBASE-9582 > Project: HBase > Issue Type: Bug > Affects Versions: 0.94.5 > Environment: hadoop 1.0.3 > Reporter: Igor Vikhrov > > I have this Scan > Scan scan = new Scan(); > scan.setCaching(50); > scan.setCacheBlocks(false); > scan.setMaxVersions(); > scan.setTimeRange(Long.valueOf(args[7] + "000"),Long.valueOf(args[8] + > "000")); > SingleColumnValueFilter filter = new > SingleColumnValueFilter(Bytes.toBytes(args[1]),Bytes.toBytes(args[2]),CompareFilter.CompareOp.EQUAL,new > BinaryComparator(Bytes.toBytes(args[3]))); > filter.setFilterIfMissing(true); > scan.setFilter(filter); > It works without any warns and errors in command line. But when regionservers > CPU is high loaded, Scan with the same parameters (Column, value, timestamps) > gives different results. For example > first time - Map output records=571374 > second time - Map output records=777620 > third time - Map output records=776099 > Regionservers log includes such WARNs: > 2013-09-19 13:29:44,827 WARN org.apache.hadoop.ipc.HBaseServer: > (responseTooSlow): > {"processingtimems":30759,"call":"next(-308003858163246780, 10), rpc > version=1, client version=29, > methodsFingerPrint=-1368823753","client":"10.10.54.22:53361","starttimems":1379582954067,"queuetimems":1,"class":"HRegionServer","responsesize":51343,"method":"next"} > and these ERRORs: > 2013-09-19 13:26:18,202 ERROR > org.apache.hadoop.hbase.regionserver.HRegionServer: > org.apache.hadoop.hbase.ipc.CallerDisconnectedException: Aborting call > next(-9095740742796333934, 10), rpc version=1, client version=29, > methodsFingerPrint=-1368823753 from 10.10.54.22:32914 after 60059 ms, since > caller disconnected > > at > org.apache.hadoop.hbase.ipc.HBaseServer$Call.throwExceptionIfCallerDisconnected(HBaseServer.java:436) > > at > org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.nextInternal(HRegion.java:3723) > > at > org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.nextRaw(HRegion.java:3643) > > at > org.apache.hadoop.hbase.regionserver.HRegion$RegionScannerImpl.nextRaw(HRegion.java:3635) > > at > org.apache.hadoop.hbase.regionserver.HRegionServer.next(HRegionServer.java:2483) > > at sun.reflect.GeneratedMethodAccessor24.invoke(Unknown Source) > > > at > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) > > at java.lang.reflect.Method.invoke(Method.java:597) > > > at > org.apache.hadoop.hbase.ipc.WritableRpcEngine$Server.call(WritableRpcEngine.java:320) > > at > org.apache.hadoop.hbase.ipc.HBaseServer$Handler.run(HBaseServer.java:1426) > > When regionservers CPU is not loaded, Scan gives same results every times. > In this case regionservers log doesn't include any WARNs. > Why does it happen? I want to be sure that Scan give me all the data that I > request no matter how CPU is using now. -- 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