I am currently experimenting with Cassandra.
On the client side (using Hector), I look at a few of these keys:
ColumnFamilyResult<String, String> result = template.queryColumns(Arrays.asList("key1","key2","key3"));
In most cases this works. But sometimes I get a timeout exception on the client:
Caused by: me.prettyprint.hector.api.exceptions.HTimedOutException: TimedOutException() at me.prettyprint.cassandra.service.ExceptionsTranslatorImpl.translate(ExceptionsTranslatorImpl.java:35) at me.prettyprint.cassandra.service.template.ThriftColumnFamilyTemplate$1.execute(ThriftColumnFamilyTemplate.java:100) at me.prettyprint.cassandra.service.template.ThriftColumnFamilyTemplate$1.execute(ThriftColumnFamilyTemplate.java:88) at me.prettyprint.cassandra.service.Operation.executeAndSetResult(Operation.java:103) at me.prettyprint.cassandra.connection.HConnectionManager.operateWithFailover(HConnectionManager.java:258) at me.prettyprint.cassandra.model.ExecutingKeyspace.doExecuteOperation(ExecutingKeyspace.java:97) at me.prettyprint.cassandra.service.template.ThriftColumnFamilyTemplate.sliceInternal(ThriftColumnFamilyTemplate.java:88) at me.prettyprint.cassandra.service.template.ThriftColumnFamilyTemplate.doExecuteSlice(ThriftColumnFamilyTemplate.java:46) at me.prettyprint.cassandra.service.template.ColumnFamilyTemplate.queryColumns(ColumnFamilyTemplate.java:113) at info.gamlor.experiments.Cassandra.readObjectByKey(ComplexCassandra.java:255) Caused by: TimedOutException() at org.apache.cassandra.thrift.Cassandra$get_slice_result.read(Cassandra.java:7772) at org.apache.cassandra.thrift.Cassandra$Client.recv_get_slice(Cassandra.java:570) at org.apache.cassandra.thrift.Cassandra$Client.get_slice(Cassandra.java:542) at me.prettyprint.cassandra.service.template.ThriftColumnFamilyTemplate$1.execute(ThriftColumnFamilyTemplate.java:95)
And this exception appears on the server:
ERROR 11:33:55,312 Exception in thread Thread[ReadStage:91,5,main] java.lang.AssertionError: DecoratedKey(4948402862350542345439897754126541659, 6932) != DecoratedKey(132475956107784875457507977471906551877, 726f6f74) in C:\tem p\cassandra\lib\cassandra\data\CassandraPolepos\ComplexObjects\CassandraPolepos-ComplexObjects-hd-2-Data.db at org.apache.cassandra.db.columniterator.SSTableSliceIterator.<init>(SSTableSliceIterator.java:58) at org.apache.cassandra.db.filter.SliceQueryFilter.getSSTableColumnIterator(SliceQueryFilter.java:66) at org.apache.cassandra.db.filter.QueryFilter.getSSTableColumnIterator(QueryFilter.java:78) at org.apache.cassandra.db.CollationController.collectAllData(CollationController.java:256) at org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:63) at org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:1331) at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1193) at org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1128) at org.apache.cassandra.db.Table.getRow(Table.java:378) at org.apache.cassandra.db.SliceFromReadCommand.getRow(SliceFromReadCommand.java:69) at org.apache.cassandra.service.StorageProxy$LocalReadRunnable.runMayThrow(StorageProxy.java:816) at org.apache.cassandra.service.StorageProxy$DroppableRunnable.run(StorageProxy.java:1250) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) at java.lang.Thread.run(Thread.java:722)
Sometimes the key values in the DecoratedKey (...) part are pages.
Any hint that I'm doing wrong. Or how to research this problem.
Thank.
cassandra hector
Gamlor Jul 24 2018-12-12T00: 00Z
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