Christian,
There are 2 use cases which are failing, and both looks to be similar
issue, basically happens in column family set with TTL.
case 1) I manage index for specific data as single row in a column family.
I set TTL to 1 second if the data need to be removed from the index row.
Under some scenario the get and count for the row key gives different
column counts. In the application if I do get I get correct set of
columns(expired columns don't return), but if I do slice query and read 100
columns at a time, the columns set with TTL returns. I am not able to
understand, what is starting this issue.
case 2) I have column family for managing locks, In this case I insert
a column with by default TTL as 15 seconds. If the transaction completes
before I remove the column by again setting TTL to 1 second.
In this case when running flush the flush hangs with following Assertion
exception.
ERROR [FlushWriter:1] 2014-02-17 11:49:29,349 CassandraDaemon.java (line
187) Exception in thread Thread[FlushWriter:1,5,main]
java.lang.AssertionError
at
org.apache.cassandra.io.sstable.SSTableWriter.rawAppend(SSTableWriter.java:198)
at
org.apache.cassandra.io.sstable.SSTableWriter.append(SSTableWriter.java:186)
at
org.apache.cassandra.db.Memtable$FlushRunnable.writeSortedContents(Memtable.java:360)
at
org.apache.cassandra.db.Memtable$FlushRunnable.runWith(Memtable.java:315)
at
org.apache.cassandra.io.util.DiskAwareRunnable.runMayThrow(DiskAwareRunnable.java:48)
at
org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:28)
at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:722)
Thanks
Mahesh
On Mon, Feb 17, 2014 at 12:43 PM, horschi <[email protected]> wrote:
> Hi Mahesh,
>
> the problem is that every column is only tombstoned for as long as the
> original column was valid.
>
> So if the last update was only valid for 1 sec, then the tombstone will
> also be valid for 1 second! If the previous was valid for a longer time,
> then this old value might reappear.
>
> Maybe you can explain why you are doing this?
>
> kind regards,
> Christian
>
>
>
> On Mon, Feb 17, 2014 at 6:18 PM, mahesh rajamani <
> [email protected]> wrote:
>
>> Christain,
>>
>> Yes. Is it a problem? Can you explain what happens in this scenario?
>>
>> Thanks
>> Mahesh
>>
>>
>> On Fri, Feb 14, 2014 at 3:07 PM, horschi <[email protected]> wrote:
>>
>>> Hi Mahesh,
>>>
>>> is it possible you are creating columns with a long TTL, then update
>>> these columns with a smaller TTL?
>>>
>>> kind regards,
>>> Christian
>>>
>>>
>>> On Fri, Feb 14, 2014 at 3:45 PM, mahesh rajamani <
>>> [email protected]> wrote:
>>>
>>>> Hi,
>>>>
>>>> I am using Cassandra 2.0.2 version. On a wide row (approx. 10000
>>>> columns), I expire few column by setting TTL as 1 second. At times these
>>>> columns show up during slice query.
>>>>
>>>> When I have this issue, running count and get commands for that row
>>>> using Cassandra cli it gives different column counts.
>>>>
>>>> But once I run flush and compact, the issue goes off and expired
>>>> columns don't show up.
>>>>
>>>> Can someone provide some help on this issue.
>>>>
>>>> --
>>>> Regards,
>>>> Mahesh Rajamani
>>>>
>>>
>>>
>>
>>
>> --
>> Regards,
>> Mahesh Rajamani
>>
>
>
--
Regards,
Mahesh Rajamani
