> Is it worth testing 0.7-branch-without-1472 to make sure of that? Dragos: if you have time, this would be helpful. If you already have a KEYS index created, you shouldn't need to re-load the data, as the file format hasn't changed.
Thanks, Stu On Sat, Nov 13, 2010 at 4:40 PM, Jonathan Ellis <jbel...@gmail.com> wrote: > 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 >
