Is it worth testing 0.7-branch-without-1472 to make sure of that? On Fri, Nov 12, 2010 at 10:28 AM, Stu Hood <stuh...@gmail.com> wrote: > Great, thanks for the variable Dragos: I'm fairly sure I broke this in the > refactoring I did in 1472 to fit in a second index type. > > > On Fri, Nov 12, 2010 at 4:03 AM, dragos cernahoschi < > dragos.cernahos...@gmail.com> wrote: > >> I confirm: the KEYS indexes have the same behavior as the KEYS_BITMAP >> indexes: time out/succeed on the same queries. >> >> By the way, the insert of my data set with KEYS_BITMAP is much faster than >> KEYS (about 5.5 times) and less gc intensive. >> >> Dragos >> >> On Tue, Nov 9, 2010 at 8:05 PM, Stu Hood <stu.h...@rackspace.com> wrote: >> >> > Interesting, thanks for the info. >> > >> > Perhaps the limitation is that index queries involving multiple clauses >> are >> > currently implemented using brute-force filtering rather than an index >> join? >> > The bitmap indexes have native support for this type of join, but it's >> not >> > being used yet. >> > >> > To confirm: have you tried the same scenario with KEYS indexes? They use >> > the same codepath for multiple index expressions, and should experience >> the >> > same timeouts. Also, can you rerun the KEYS_BITMAP test with DEBUG >> logging >> > enabled, to ensure that we aren't going into some kind of infinite loop? >> > >> > Thanks for the help, >> > Stu >> > >> > -----Original Message----- >> > From: "dragos cernahoschi" <dragos.cernahos...@gmail.com> >> > Sent: Tuesday, November 9, 2010 11:50am >> > To: dev@cassandra.apache.org >> > Subject: Re: CASSANDRA-1472 (bitmap indexes) >> > >> > I'm running the query on three columns with cardinalities: 22, 17 and >> > 10. >> > Interesting, if combining columns with cardinalities: >> > >> > 22 + 17 => no exception >> > 22 + 10 => no exception >> > 10 + 17 => timed out exception >> > 22 + 17 + 10 => timed out exception >> > >> > >> > On Tue, Nov 9, 2010 at 6:29 PM, Stu Hood <stu.h...@rackspace.com> wrote: >> > >> > > Can you tell me a little bit about your key distribution? How many >> unique >> > > values are indexed (the cardinality)? >> > > >> > > Until the OrBiC projection I mention on 1472 is implemented, the >> > > bitmap >> > > secondary indexes will perform terribly for high cardinality datasets. >> > > >> > > Thanks! >> > > >> > > >> > > -----Original Message----- >> > > From: "dragos cernahoschi" <dragos.cernahos...@gmail.com> >> > > Sent: Tuesday, November 9, 2010 10:14am >> > > To: dev@cassandra.apache.org >> > > Subject: Re: CASSANDRA-1472 (bitmap indexes) >> > > >> > > Meantime the number of SSTable(s) reduced to just 7. Initially the >> > > compaction thread suffered the same problem of "too many open files" >> and >> > > couldn't do any compaction. >> > > >> > > But I'm still not able to run my tests: TimedOutException :( >> > > >> > > On Tue, Nov 9, 2010 at 5:51 PM, Stu Hood <stu.h...@rackspace.com> >> wrote: >> > > >> > > > Hmm, 500 sstables is definitely a degenerate case: did you disable >> > > > compaction? By default, Cassandra strives to keep the sstable count >> > below >> > > > ~32, since accesses to separate sstables require seeks. >> > > > >> > > > In this case, the query will seek 500 times to check the secondary >> > index >> > > > for each sstable: if it finds matches it will need to seek to find >> them >> > > in >> > > > the primary index, and seek again for the data file. >> > > > >> > > > -----Original Message----- >> > > > From: "dragos cernahoschi" <dragos.cernahos...@gmail.com> >> > > > Sent: Tuesday, November 9, 2010 5:33am >> > > > To: dev@cassandra.apache.org >> > > > Subject: Re: CASSANDRA-1472 (bitmap indexes) >> > > > >> > > > There are about 500 SSTables (12GB of data including index data, >> > > > statistics...) The source data file had about 3GB/26 million rows. >> > > > >> > > > I only test with EQ expressions for now. >> > > > >> > > > Increasing the file limit resolved the problem, but now I'm getting >> > > > TimedOutException(s) from thrift when "querying" even with slice >> > > > size >> > of >> > > 1. >> > > > Is my machine too small (core 2 duo 2.93 2GB RAM Ubuntu 10.04) for >> such >> > a >> > > > test? >> > > > >> > > > I really have some interesting sets of data to test indexes with and >> I >> > > want >> > > > to make a comparison between ordinary indexes and bitmap indexes. >> > > > >> > > > Thank you, >> > > > Dragos >> > > > >> > > > On Mon, Nov 8, 2010 at 6:42 PM, Stu Hood <stu.h...@rackspace.com> >> > wrote: >> > > > >> > > > > Dragos, >> > > > > >> > > > > How many SSTables did you have on disk, and were any of your index >> > > > > expressions GT(E)/LT(E)? >> > > > > >> > > > > I expect that you are bumping into a limitation of the current >> > > > > implementation: it opens up to 128 file-handles per SSTable in the >> > > worst >> > > > > case for a GT/LT query (one per index bucket). >> > > > > >> > > > > A future version might remove that requirement, but for now, you >> > should >> > > > > probably bump the file handle limit on your machine to at least >> 2^16. >> > > > > >> > > > > Thanks, >> > > > > Stu >> > > > > >> > > > > >> > > > > -----Original Message----- >> > > > > From: "dragos cernahoschi" <dragos.cernahos...@gmail.com> >> > > > > Sent: Monday, November 8, 2010 10:05am >> > > > > To: dev@cassandra.apache.org >> > > > > Subject: CASSANDRA-1472 (bitmap indexes) >> > > > > >> > > > > Hi, >> > > > > >> > > > > I've got an exception during the following test: >> > > > > >> > > > > test machine: core 2 duo 2.93 2GB RAM Ubuntu 10.04 >> > > > > >> > > > > test scenario: >> > > > > - 1 column family >> > > > > - about 15 columns >> > > > > - 7 indexed columns (bitmap) >> > > > > - 26 million rows (insert operation went fine) >> > > > > - thrift "query" on 3 of the indexed columns with >> get_indexed_slices >> > > > > (count: >> > > > > 100) >> > > > > - got the following exception: >> > > > > >> > > > > 10/11/08 17:52:40 ERROR service.AbstractCassandraDaemon: Fatal >> > > exception >> > > > in >> > > > > thread Thread[ReadStage:3,5,main] >> > > > > java.io.IOError: java.io.FileNotFoundException: >> > > > > /home/dragos/cassandra/data/keyspace/visit-e-814-4-Bitidx.db (Too >> > many >> > > > open >> > > > > files) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.sstable.bitidx.SegmentIterator.open(SegmentIterator.java:78) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.sstable.bitidx.BitmapIndexReader.openBin(BitmapIndexReader.java:226) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.sstable.bitidx.BitmapIndexReader.iterator(BitmapIndexReader.java:214) >> > > > > at >> > > > > >> > > > >> > > >> > >> org.apache.cassandra.io.sstable.SSTableReader.scan(SSTableReader.java:523) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.db.secindex.KeysBitmapIndex.iterator(KeysBitmapIndex.java:103) >> > > > > at >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.db.ColumnFamilyStore.scan(ColumnFamilyStore.java:1371) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.service.IndexScanVerbHandler.doVerb(IndexScanVerbHandler.java:41) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.net.MessageDeliveryTask.run(MessageDeliveryTask.java:51) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) >> > > > > at java.lang.Thread.run(Thread.java:662) >> > > > > Caused by: java.io.FileNotFoundException: >> > > > > /home/dragos/cassandra/data/keyspace/visit-e-814-4-Bitidx.db (Too >> > many >> > > > open >> > > > > files) >> > > > > at java.io.FileInputStream.open(Native Method) >> > > > > at java.io.FileInputStream.<init>(FileInputStream.java:106) >> > > > > at >> > > > > >> > > >> org.apache.avro.file.SeekableFileInput.<init>(SeekableFileInput.java:29) >> > > > > at >> > > org.apache.avro.file.DataFileReader.<init>(DataFileReader.java:38) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.sstable.bitidx.SegmentIterator.open(SegmentIterator.java:72) >> > > > > ... 10 more >> > > > > 10/11/08 17:52:40 ERROR service.AbstractCassandraDaemon: Fatal >> > > exception >> > > > in >> > > > > thread Thread[ReadStage:2,5,main] >> > > > > java.io.IOError: java.io.FileNotFoundException: >> > > > > /home/dragos/cassandra/data/keyspace/visit-e-1018-Index.db (Too >> many >> > > open >> > > > > files) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.util.BufferedSegmentedFile.getSegment(BufferedSegmentedFile.java:68) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.util.SegmentedFile$SegmentIterator.next(SegmentedFile.java:129) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.util.SegmentedFile$SegmentIterator.next(SegmentedFile.java:1) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.sstable.SSTableReader.getPosition(SSTableReader.java:455) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.sstable.SSTableReader.getFileDataInput(SSTableReader.java:572) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.db.columniterator.SSTableSliceIterator.<init>(SSTableSliceIterator.java:49) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.db.filter.SliceQueryFilter.getSSTableColumnIterator(SliceQueryFilter.java:72) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.db.filter.QueryFilter.getSSTableColumnIterator(QueryFilter.java:84) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:1190) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1082) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1052) >> > > > > at >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.db.ColumnFamilyStore.scan(ColumnFamilyStore.java:1378) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.service.IndexScanVerbHandler.doVerb(IndexScanVerbHandler.java:41) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.net.MessageDeliveryTask.run(MessageDeliveryTask.java:51) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) >> > > > > at java.lang.Thread.run(Thread.java:662) >> > > > > Caused by: java.io.FileNotFoundException: >> > > > > /home/dragos/cassandra/data/keyspace/visit-e-1018-Index.db (Too >> many >> > > open >> > > > > files) >> > > > > at java.io.RandomAccessFile.open(Native Method) >> > > > > at java.io.RandomAccessFile.<init>(RandomAccessFile.java:212) >> > > > > at java.io.RandomAccessFile.<init>(RandomAccessFile.java:98) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.util.BufferedRandomAccessFile.<init>(BufferedRandomAccessFile.java:142) >> > > > > at >> > > > > >> > > > > >> > > > >> > > >> > >> >> org.apache.cassandra.io.util.BufferedSegmentedFile.getSegment(BufferedSegmentedFile.java:62) >> > > > > ... 16 more >> > > > > >> > > > > The same test worked fine with 1 million rows. >> > > > > >> > > > > >> > > > > >> > > > >> > > > >> > > > >> > > >> > > >> > > >> > >> > >> > >> >
-- Jonathan Ellis Project Chair, Apache Cassandra co-founder of Riptano, the source for professional Cassandra support http://riptano.com
