Compaction did not help too.
> On Oct 9, 2015, at 1:01 PM, Nazario Parsacala <dodongj...@gmail.com> wrote:
>
> So I upgraded to 2.2.2 and change the compaction strategy from
> DateTieredCompactionStrategy to LeveledCompactionStrategy. But the problem
> still exists.
> At the start we were getting responses around 80 to a couple of hundred of
> ms. But after 1.5 hours of running, it is now hitting 1447 ms. I think this
> will degrade some more as time progresses. I will let this run a couple of
> hours more and will also try to force compaction.
>
> BTW, with 2.2.2 I am getting the following exceptions. Not sure if there is
> already a bug report on this.
>
> Caused by: java.io.IOException: Seek position 182054 is not within mmap
> segment (seg offs: 0, length: 182054)
> at
> org.apache.cassandra.io.util.ByteBufferDataInput.seek(ByteBufferDataInput.java:47)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.io.util.AbstractDataInput.skipBytes(AbstractDataInput.java:33)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.io.util.FileUtils.skipBytesFully(FileUtils.java:405)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.RowIndexEntry$Serializer.skipPromotedIndex(RowIndexEntry.java:164)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.RowIndexEntry$Serializer.skip(RowIndexEntry.java:155)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.io.sstable.format.big.BigTableReader.getPosition(BigTableReader.java:244)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> ... 17 common frames omitted
> WARN [SharedPool-Worker-42] 2015-10-09 12:54:57,221
> AbstractTracingAwareExecutorService.java:169 - Uncaught exception on thread
> Thread[SharedPool-Worker-42,5,main]: {}
> java.lang.RuntimeException:
> org.apache.cassandra.io.sstable.CorruptSSTableException: java.io.IOException:
> Seek position 182054 is not within mmap segment (seg offs: 0, length: 182054)
> at
> org.apache.cassandra.service.StorageProxy$DroppableRunnable.run(StorageProxy.java:2187)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
> ~[na:1.8.0_60]
> at
> org.apache.cassandra.concurrent.AbstractTracingAwareExecutorService$FutureTask.run(AbstractTracingAwareExecutorService.java:164)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at org.apache.cassandra.concurrent.SEPWorker.run(SEPWorker.java:105)
> [apache-cassandra-2.2.2.jar:2.2.2]
> at java.lang.Thread.run(Thread.java:745) [na:1.8.0_60]
> Caused by: org.apache.cassandra.io.sstable.CorruptSSTableException:
> java.io.IOException: Seek position 182054 is not within mmap segment (seg
> offs: 0, length: 182054)
> at
> org.apache.cassandra.io.sstable.format.big.BigTableReader.getPosition(BigTableReader.java:250)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.io.sstable.format.SSTableReader.getPosition(SSTableReader.java:1558)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.io.sstable.format.big.SSTableSliceIterator.<init>(SSTableSliceIterator.java:42)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.io.sstable.format.big.BigTableReader.iterator(BigTableReader.java:75)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.filter.SliceQueryFilter.getSSTableColumnIterator(SliceQueryFilter.java:246)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.filter.QueryFilter.getSSTableColumnIterator(QueryFilter.java:62)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.CollationController.collectAllData(CollationController.java:270)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.CollationController.getTopLevelColumns(CollationController.java:64)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.ColumnFamilyStore.getTopLevelColumns(ColumnFamilyStore.java:2004)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.ColumnFamilyStore.getColumnFamily(ColumnFamilyStore.java:1808)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at org.apache.cassandra.db.Keyspace.getRow(Keyspace.java:360)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.SliceFromReadCommand.getRow(SliceFromReadCommand.java:85)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.service.StorageProxy$LocalReadRunnable.runMayThrow(StorageProxy.java:1537)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.service.StorageProxy$DroppableRunnable.run(StorageProxy.java:2183)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> ... 4 common frames omitted
> Caused by: java.io.IOException: Seek position 182054 is not within mmap
> segment (seg offs: 0, length: 182054)
> at
> org.apache.cassandra.io.util.ByteBufferDataInput.seek(ByteBufferDataInput.java:47)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.io.util.AbstractDataInput.skipBytes(AbstractDataInput.java:33)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.io.util.FileUtils.skipBytesFully(FileUtils.java:405)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.RowIndexEntry$Serializer.skipPromotedIndex(RowIndexEntry.java:164)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.db.RowIndexEntry$Serializer.skip(RowIndexEntry.java:155)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
> at
> org.apache.cassandra.io.sstable.format.big.BigTableReader.getPosition(BigTableReader.java:244)
> ~[apache-cassandra-2.2.2.jar:2.2.2]
>
>
>
>
>> On Oct 9, 2015, at 9:26 AM, Carlos Alonso <i...@mrcalonso.com
>> <mailto:i...@mrcalonso.com>> wrote:
>>
>> Yeah, I was about to suggest the compaction strategy too. Leveled compaction
>> sounds like a better fit when records are being updated
>>
>> Carlos Alonso | Software Engineer | @calonso <https://twitter.com/calonso>
>>
>> On 8 October 2015 at 22:35, Tyler Hobbs <ty...@datastax.com
>> <mailto:ty...@datastax.com>> wrote:
>> Upgrade to 2.2.2. Your sstables are probably not compacting due to
>> CASSANDRA-10270 <https://issues.apache.org/jira/browse/CASSANDRA-10270>,
>> which was fixed in 2.2.2.
>>
>> Additionally, you may want to look into using leveled compaction
>> (http://www.datastax.com/dev/blog/when-to-use-leveled-compaction
>> <http://www.datastax.com/dev/blog/when-to-use-leveled-compaction>).
>>
>> On Thu, Oct 8, 2015 at 4:27 PM, Nazario Parsacala <dodongj...@gmail.com
>> <mailto:dodongj...@gmail.com>> wrote:
>>
>> Hi,
>>
>> so we are developing a system that computes profile of things that it
>> observes. The observation comes in form of events. Each thing that it
>> observe has an id and each thing has a set of subthings in it which has
>> measurement of some kind. Roughly there are about 500 subthings within each
>> thing. We receive events containing measurements of these 500 subthings
>> every 10 seconds or so.
>>
>> So as we receive events, we read the old profile value, calculate the new
>> profile based on the new value and save it back. We use the following schema
>> to hold the profile.
>>
>> CREATE TABLE myprofile (
>> id text,
>> month text,
>> day text,
>> hour text,
>> subthings text,
>> lastvalue double,
>> count int,
>> stddev double,
>> PRIMARY KEY ((id, month, day, hour), subthings)
>> ) WITH CLUSTERING ORDER BY (subthings ASC) );
>>
>>
>> This profile will then be use for certain analytics that can use in the
>> context of the ‘thing’ or in the context of specific thing and subthing.
>>
>> A profile can be defined as monthly, daily, hourly. So in case of monthly
>> the month will be set to the current month (i.e. ‘Oct’) and the day and hour
>> will be set to empty ‘’ string.
>>
>>
>> The problem that we have observed is that over time (actually in just a
>> matter of hours) we will see a huge degradation of query response for the
>> monthly profile. At the start it will be respinding in 10-100 ms and after a
>> couple of hours it will go to 2000-3000 ms . If you leave it for a couple of
>> days you will start experiencing readtimeouts . The query is basically just :
>>
>> select * from myprofile where id=‘1’ and month=‘Oct’ and day=‘’ and hour=‘'
>>
>> This will have only about 500 rows or so.
>>
>>
>> I believe that this is cause by the fact there are multiple updates done to
>> this specific partition. So what do we think can be done to resolve this ?
>>
>> BTW, I am using Cassandra 2.2.1 . And since this is a test , this is just
>> running on a single node.
>>
>>
>>
>>
>>
>>
>>
>> --
>> Tyler Hobbs
>> DataStax <http://datastax.com/>
>>
>
