Jonathan, I have downloaded 0.6.8 and the iteration problem is fixed. Thanks, Eric
-----Original Message----- From: Jonathan Ellis [mailto:jbel...@gmail.com] Sent: donderdag 11 november 2010 23:05 To: user Subject: Re: iteration does not yield all data with consistency ONE Can you try with the latest 0.6 svn branch? https://svn.apache.org/repos/asf/cassandra/branches/cassandra-0.6 It may be caused by https://issues.apache.org/jira/browse/CASSANDRA-1722 which is fixed there. On Thu, Nov 11, 2010 at 4:56 AM, Eric van Orsouw <eric.van.ors...@eventis.nl> wrote: > I have tried it with RF=1 and 2 nodes and the result was the same. > In this case I am not able to query anything, regardless the consistency > level. > > I have conducted some more tests with 4 nodes and RF=2 and before each test I > also completely cleared all datafiles (data/commit/saved_cache). > Each time I do this the nodes get different locations on the ring and the > noticed behavior is different (but similar) each time. > I have added the details for 2 concrete scenario; > > ---- > 1) clear all 3 data directories for all nodes > 2) startup all nodes; the ring is; > > # bin/nodetool -h 172.16.21.12 ring > Address Status Load Range > Ring > 81296677393575658129031223607666487650 > 172.16.21.12 Up 489 bytes 61644956546475371096781179489550878842 > |<--| > 172.16.21.14 Up 489 bytes 63811055530446251457866768401307252614 > | | > 172.16.21.13 Up 489 bytes 71622328744148061175473750202165524046 > | | > 172.16.21.11 Up 489 bytes 81296677393575658129031223607666487650 > |-->| > > 3) I use the following ColumnFamily <ColumnFamily Name="Customers" > ColumnType="Super" CompareWith="AsciiType"/> > And add the following rows (key and values utf8 strings) > Customer['1'].simple.id='1' > Customer['2'].simple.id='2' > Customer['3'].simple.id='3' > Customer['4'].simple.id='4' > > 4) Iterating over the columns now yield; > Iterating Nodes .11 thru.13 ==> all rows, regardless of consistency > level > Iterating Node.14 ==> only row '3' and '4' with consistency > level ONE, all rows with consistency level All > > ---- > Repating all process steps again yields the following ring and iteration > results > # bin/nodetool -h 172.16.21.11 ring > Address Status Load Range > Ring > 157208721428268855331814529932509412075 > 172.16.21.11 Up 489 bytes 18662665007498667259581716616851966032 > |<--| > 172.16.21.13 Up 489 bytes > 125997322478065775200568923383951796531 | | > 172.16.21.12 Up 489 bytes > 148125235552363592916130178190645177045 | | > 172.16.21.14 Up 489 bytes > 157208721428268855331814529932509412075 |-->| > > Iterating Nodes .11 .12 .14 ==> no data with consistency level One, > all rows with consistency level All > Iterating Node .13 ==> only row '3' and '4' with consistency > level ONE, all rows with consistency level All > > I appears to me there is an inconsistency somewhere, I hope this info helps. > > Eric > > > -----Original Message----- > From: Jonathan Ellis [mailto:jbel...@gmail.com] > Sent: woensdag 10 november 2010 17:48 > To: user > Subject: Re: iteration does not yield all data with consistency ONE > > Interesting. Does it simplify further to RF=1 and 2 nodes? > > On Wed, Nov 10, 2010 at 8:58 AM, Eric van Orsouw > <eric.van.ors...@eventis.nl> wrote: >> No, all nodes were up and running while the single key was inserted. >> The insert however was with consistency One. I assume however that the >> replicas are still written in this case. >> It is btw also very reproducible. >> >> -----Original Message----- >> From: Jonathan Ellis [mailto:jbel...@gmail.com] >> Sent: woensdag 10 november 2010 15:44 >> To: user >> Subject: Re: iteration does not yield all data with consistency ONE >> >> Was the node that should have the other replica of this row down when >> it was inserted? >> >> On Wed, Nov 10, 2010 at 6:08 AM, Eric van Orsouw >> <eric.van.ors...@eventis.nl> wrote: >>> >>> Hello, >>> >>> >>> >>> We have a cluster of 4 nodes (0.6.6) and use the random partitioner and a >>> replication of 2. >>> >>> When I insert a number of rows I can always retrieve them by their explicit >>> id (get_range_slices("<key>","", 1). >>> >>> Playing with consistency levels and temporarily shutting down a Cassandra >>> node all yields the expected result. >>> >>> >>> >>> However when I use get_range_slices("","", n) to iterate over all rows, I >>> sometimes don't get anything (depending on the node). >>> >>> >>> >>> I then reduced the problem to inserting just a single row. >>> >>> Specifically, the 'iteration' only seems to succeed when I issue the >>> request to the node that contains the first copy. >>> >>> I Discovered that when I iterate using a consistency level of Quorum/All >>> the iteration always succeeds and I properly get the one row. >>> >>> >>> >>> So a solution would be to always use consistency level One/All but that has >>> a performance penalty. >>> >>> >>> >>> Can anyone explain why iterating using get_range_slices("","",n) does not >>> always function with consistency level One on all nodes? >>> >>> >>> >>> Thanks, >>> >>> Eric >>> >>> >>> >>> P.S. To rule out any discussion on whether or not to use iteration in the >>> first place, we only plan to use it for backup and periodic cleanup cycles. >> >> >> -- >> Jonathan Ellis >> Project Chair, Apache Cassandra >> co-founder of Riptano, the source for professional Cassandra support >> http://riptano.com >> > > > > -- > Jonathan Ellis > Project Chair, Apache Cassandra > co-founder of Riptano, the source for professional Cassandra support > http://riptano.com > -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of Riptano, the source for professional Cassandra support http://riptano.com
