Hi Jonathan in what scenario will there be only one version of a row? and for this scenario, does this mean that these tombstone records will never ever be deleted?
Also on a higher level, what I am trying to do is provide some garbage collection of entries in the cassandra hash that have expired.(Kind of like time-to-live functionality for records in Cassandra). Do you have any insights on how that can be accomplished. On Wed, Oct 21, 2009 at 12:30 PM, Ramzi Rabah <rra...@playdom.com> wrote: > I opened https://issues.apache.org/jira/browse/CASSANDRA-507 > > Ray > > On Wed, Oct 21, 2009 at 12:07 PM, Jonathan Ellis <jbel...@gmail.com> wrote: >> The compaction code removes tombstones, and it runs whenever you have >> enough sstable fragments. >> >> I think I know what is happening -- as an optimization, if there is >> only one version of a row it will just copy it to the new sstable. >> This means it won't clean out tombstones. >> >> Can you file a bug at https://issues.apache.org/jira/browse/CASSANDRA ? >> >> -Jonathan >> >> On Wed, Oct 21, 2009 at 2:01 PM, Ramzi Rabah <rra...@playdom.com> wrote: >>> Hi Jonathan I am still running into the timeout issue even after >>> reducing the GCGraceSeconds to 1 hour (we have tons of deletes >>> happening in our app). Which part of Cassandra >>> is responsible for deleting the tombstone records and how often does it run. >>> >>> >>> On Tue, Oct 20, 2009 at 12:02 PM, Ramzi Rabah <rra...@playdom.com> wrote: >>>> Thank you so much Jonathan. >>>> >>>> Data is test data so I'll just wipe it out and restart after updating >>>> GCGraceSeconds. >>>> Thanks for your help. >>>> >>>> Ray >>>> >>>> On Tue, Oct 20, 2009 at 11:39 AM, Jonathan Ellis <jbel...@gmail.com> wrote: >>>>> The problem is you have a few MB of actual data and a few hundred MB >>>>> of tombstones (data marked deleted). So what happens is get_key_range >>>>> spends a long, long time iterating through the tombstoned rows, >>>>> looking for keys that actually still exist. >>>>> >>>>> We're going to redesign this for CASSANDRA-344, but for the 0.4 >>>>> series, you should restart with GCGraceSeconds much lower (e.g. 3600), >>>>> delete your old data files, and reload your data fresh. (Instead of >>>>> reloading, you can use "nodeprobe compact" on each node to force a >>>>> major compaction but it will take much longer since you have so many >>>>> tombstones). >>>>> >>>>> -Jonathan >>>>> >>>>> On Mon, Oct 19, 2009 at 10:45 PM, Ramzi Rabah <rra...@playdom.com> wrote: >>>>>> Hi Jonathan: >>>>>> >>>>>> Here is the storage_conf.xml for one of the servers >>>>>> http://email.slicezero.com/storage-conf.xml >>>>>> >>>>>> and here is the zipped data: >>>>>> http://email.slicezero.com/datastoreDeletion.tgz >>>>>> >>>>>> Thanks >>>>>> Ray >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> On Mon, Oct 19, 2009 at 8:30 PM, Jonathan Ellis <jbel...@gmail.com> >>>>>> wrote: >>>>>>> Yes, please. You'll probably have to use something like >>>>>>> http://www.getdropbox.com/ if you don't have a public web server to >>>>>>> stash it temporarily. >>>>>>> >>>>>>> On Mon, Oct 19, 2009 at 10:28 PM, Ramzi Rabah <rra...@playdom.com> >>>>>>> wrote: >>>>>>>> Hi Jonathan the data is about 60 MB. Would you like me to send it to >>>>>>>> you? >>>>>>>> >>>>>>>> >>>>>>>> On Mon, Oct 19, 2009 at 8:20 PM, Jonathan Ellis <jbel...@gmail.com> >>>>>>>> wrote: >>>>>>>>> Is the data on 6, 9, or 10 small enough that you could tar.gz it up >>>>>>>>> for me to use to reproduce over here? >>>>>>>>> >>>>>>>>> On Mon, Oct 19, 2009 at 10:17 PM, Ramzi Rabah <rra...@playdom.com> >>>>>>>>> wrote: >>>>>>>>>> So my cluster has 4 nodes node6, node8, node9 and node10. I turned >>>>>>>>>> them all off. >>>>>>>>>> 1- I started node6 by itself and still got the problem. >>>>>>>>>> 2- I started node8 by itself and it ran fine (returned no keys) >>>>>>>>>> 3- I started node9 by itself and still got the problem. >>>>>>>>>> 4- I started node10 by itself and still got the problem. >>>>>>>>>> >>>>>>>>>> Ray >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Mon, Oct 19, 2009 at 7:44 PM, Jonathan Ellis <jbel...@gmail.com> >>>>>>>>>> wrote: >>>>>>>>>>> That's really strange... Can you reproduce on a single-node >>>>>>>>>>> cluster? >>>>>>>>>>> >>>>>>>>>>> On Mon, Oct 19, 2009 at 9:34 PM, Ramzi Rabah <rra...@playdom.com> >>>>>>>>>>> wrote: >>>>>>>>>>>> The rows are very small. There are a handful of columns per row >>>>>>>>>>>> (approximately about 4-5 columns per row). >>>>>>>>>>>> Each column has a name which is a String (20-30 characters long), >>>>>>>>>>>> and >>>>>>>>>>>> the value is an empty array of bytes (new byte[0]). >>>>>>>>>>>> I just use the names of the columns, and don't need to store any >>>>>>>>>>>> values in this Column Family. >>>>>>>>>>>> >>>>>>>>>>>> -- Ray >>>>>>>>>>>> >>>>>>>>>>>> On Mon, Oct 19, 2009 at 7:24 PM, Jonathan Ellis >>>>>>>>>>>> <jbel...@gmail.com> wrote: >>>>>>>>>>>>> Can you tell me anything about the nature of your rows? Many/few >>>>>>>>>>>>> columns? Large/small column values? >>>>>>>>>>>>> >>>>>>>>>>>>> On Mon, Oct 19, 2009 at 9:17 PM, Ramzi Rabah <rra...@playdom.com> >>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> Hi Jonathan >>>>>>>>>>>>>> I actually spoke too early. Now even if I restart the servers it >>>>>>>>>>>>>> still >>>>>>>>>>>>>> gives a timeout exception. >>>>>>>>>>>>>> As far as the sstable files are, not sure which ones are the >>>>>>>>>>>>>> sstables, >>>>>>>>>>>>>> but here is the list of files in the data directory that are >>>>>>>>>>>>>> prepended >>>>>>>>>>>>>> with the column family name: >>>>>>>>>>>>>> DatastoreDeletionSchedule-1-Data.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-1-Filter.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-1-Index.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-5-Data.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-5-Filter.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-5-Index.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-7-Data.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-7-Filter.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-7-Index.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-8-Data.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-8-Filter.db >>>>>>>>>>>>>> DatastoreDeletionSchedule-8-Index.db >>>>>>>>>>>>>> >>>>>>>>>>>>>> I am not currently doing any system stat collection. >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Mon, Oct 19, 2009 at 6:41 PM, Jonathan Ellis >>>>>>>>>>>>>> <jbel...@gmail.com> wrote: >>>>>>>>>>>>>>> How many sstable files are in the data directories for the >>>>>>>>>>>>>>> columnfamily you are querying? >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> How many are there after you restart and it is happy? >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Are you doing system stat collection with munin or ganglia or >>>>>>>>>>>>>>> some such? >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Mon, Oct 19, 2009 at 8:25 PM, Ramzi Rabah >>>>>>>>>>>>>>> <rra...@playdom.com> wrote: >>>>>>>>>>>>>>>> Hi Jonathan I updated to 4.1 and I still get the same >>>>>>>>>>>>>>>> exception when I >>>>>>>>>>>>>>>> call get_key_range. >>>>>>>>>>>>>>>> I checked all the server logs, and there is only one exception >>>>>>>>>>>>>>>> being >>>>>>>>>>>>>>>> thrown by whichever server I am connecting to. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thanks >>>>>>>>>>>>>>>> Ray >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Mon, Oct 19, 2009 at 4:52 PM, Jonathan Ellis >>>>>>>>>>>>>>>> <jbel...@gmail.com> wrote: >>>>>>>>>>>>>>>>> No, it's smart enough to avoid scanning. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Mon, Oct 19, 2009 at 6:49 PM, Ramzi Rabah >>>>>>>>>>>>>>>>> <rra...@playdom.com> wrote: >>>>>>>>>>>>>>>>>> Hi Jonathan thanks for the reply, I will update the code to >>>>>>>>>>>>>>>>>> 0.4.1 and >>>>>>>>>>>>>>>>>> will check all the logs on all the machines. >>>>>>>>>>>>>>>>>> Just a simple question, when you do a get_key_range and you >>>>>>>>>>>>>>>>>> specify "" >>>>>>>>>>>>>>>>>> and "" for start and end, and the limit is 25, if there are >>>>>>>>>>>>>>>>>> too many >>>>>>>>>>>>>>>>>> entries, does it do a scan to find out the start or is it >>>>>>>>>>>>>>>>>> smart enough >>>>>>>>>>>>>>>>>> to know what the start key is? >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On Mon, Oct 19, 2009 at 4:42 PM, Jonathan Ellis >>>>>>>>>>>>>>>>>> <jbel...@gmail.com> wrote: >>>>>>>>>>>>>>>>>>> You should check the other nodes for potential exceptions >>>>>>>>>>>>>>>>>>> keeping them >>>>>>>>>>>>>>>>>>> from replying. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Without seeing that it's hard to say if this is caused by >>>>>>>>>>>>>>>>>>> an old bug, >>>>>>>>>>>>>>>>>>> but you should definitely upgrade to 0.4.1 either way :) >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On Mon, Oct 19, 2009 at 5:51 PM, Ramzi Rabah >>>>>>>>>>>>>>>>>>> <rra...@playdom.com> wrote: >>>>>>>>>>>>>>>>>>>> Hello all, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I am running into problems with get_key_range. I have >>>>>>>>>>>>>>>>>>>> OrderPreservingPartitioner defined in storage-conf.xml and >>>>>>>>>>>>>>>>>>>> I am using >>>>>>>>>>>>>>>>>>>> a columnfamily that looks like >>>>>>>>>>>>>>>>>>>> <ColumnFamily CompareWith="BytesType" >>>>>>>>>>>>>>>>>>>> Name="DatastoreDeletionSchedule" >>>>>>>>>>>>>>>>>>>> /> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> My command is client.get_key_range("Keyspace1", >>>>>>>>>>>>>>>>>>>> "DatastoreDeletionSchedule", >>>>>>>>>>>>>>>>>>>> "", "", 25, ConsistencyLevel.ONE); >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> It usually works fine but after a day or so from server >>>>>>>>>>>>>>>>>>>> writes into >>>>>>>>>>>>>>>>>>>> this column family, I started getting >>>>>>>>>>>>>>>>>>>> ERROR [pool-1-thread-36] 2009-10-19 17:24:28,223 >>>>>>>>>>>>>>>>>>>> Cassandra.java (line >>>>>>>>>>>>>>>>>>>> 770) Internal error processing get_key_range >>>>>>>>>>>>>>>>>>>> java.lang.RuntimeException: >>>>>>>>>>>>>>>>>>>> java.util.concurrent.TimeoutException: >>>>>>>>>>>>>>>>>>>> Operation timed out. >>>>>>>>>>>>>>>>>>>> at >>>>>>>>>>>>>>>>>>>> org.apache.cassandra.service.StorageProxy.getKeyRange(StorageProxy.java:560) >>>>>>>>>>>>>>>>>>>> at >>>>>>>>>>>>>>>>>>>> org.apache.cassandra.service.CassandraServer.get_key_range(CassandraServer.java:595) >>>>>>>>>>>>>>>>>>>> at >>>>>>>>>>>>>>>>>>>> org.apache.cassandra.service.Cassandra$Processor$get_key_range.process(Cassandra.java:766) >>>>>>>>>>>>>>>>>>>> at >>>>>>>>>>>>>>>>>>>> org.apache.cassandra.service.Cassandra$Processor.process(Cassandra.java:609) >>>>>>>>>>>>>>>>>>>> at >>>>>>>>>>>>>>>>>>>> org.apache.thrift.server.TThreadPoolServer$WorkerProcess.run(TThreadPoolServer.java:253) >>>>>>>>>>>>>>>>>>>> at >>>>>>>>>>>>>>>>>>>> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:885) >>>>>>>>>>>>>>>>>>>> at >>>>>>>>>>>>>>>>>>>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907) >>>>>>>>>>>>>>>>>>>> at java.lang.Thread.run(Thread.java:619) >>>>>>>>>>>>>>>>>>>> Caused by: java.util.concurrent.TimeoutException: >>>>>>>>>>>>>>>>>>>> Operation timed out. >>>>>>>>>>>>>>>>>>>> at >>>>>>>>>>>>>>>>>>>> org.apache.cassandra.net.AsyncResult.get(AsyncResult.java:97) >>>>>>>>>>>>>>>>>>>> at >>>>>>>>>>>>>>>>>>>> org.apache.cassandra.service.StorageProxy.getKeyRange(StorageProxy.java:556) >>>>>>>>>>>>>>>>>>>> ... 7 more >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I still get the timeout exceptions even though the servers >>>>>>>>>>>>>>>>>>>> have been >>>>>>>>>>>>>>>>>>>> idle for 2 days. When I restart the cassandra servers, it >>>>>>>>>>>>>>>>>>>> seems to >>>>>>>>>>>>>>>>>>>> work fine again. Any ideas what could be wrong? >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> By the way, I am using >>>>>>>>>>>>>>>>>>>> version:apache-cassandra-incubating-0.4.0-rc2 >>>>>>>>>>>>>>>>>>>> Not sure if this is fixed in the 0.4.1 version >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thanks >>>>>>>>>>>>>>>>>>>> Ray >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>> >>>>>> >>>>> >>>> >>> >> >
