Hi,

we have been running a system on Cassandra 0.7 heavily relying on secondary 
indexes for columns with TTL.
This has been working like a charm, but we are trying hard to move forward with 
Cassandra and are struggling at that point:

When we put our data into a new cluster (any 1.1.x version - currently 1.1.5) , 
rebuild indexes and run our system, everything seems to work good - until in 
some point of time index queries do not return any data at all anymore (note 
that the TTL has not yet expired for several months).
Rebuilding the index gives us back the data for a couple of minutes - then it 
vanishes again.

What seems strange is that compaction apparently is very aggressive:

INFO [CompactionExecutor:181] 2012-09-13 12:58:37,443 CompactionTask.java (line
221) Compacted to [/var/lib/cassandra/data/Eventstore/EventsByItem/Eventstore-E
ventsByItem.ebi_eventtypeIndex-he-10-Data.db,].  78,623,000 to 373,348 (~0% of o
riginal) bytes for 83 keys at 0.000280MB/s.  Time: 1,272,883ms.


Actually we have switched to LeveledCompaction. Could it be that leveled 
compaction does not play nice with indexes?


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