Looks like it may have been overlooked when CF directories were added, can you create a ticket on https://issues.apache.org/jira/browse/CASSANDRA

Aaron Morton
Freelance Developer

On 3/07/2012, at 1:15 AM, Pieter Callewaert wrote:

While I was typing my mail I had the idea to try with the new directory layout.
It seems you have to change the parameter settings from 1.0 to 1.1
In 1.0:
Param 1: <keyspace name>
Param 2: <datafile name>
In 1.1:
Param 1: <keyspace name>
Param 2: <column family name>/<datafile name>
Donít know if this is a bug or a breaking change ?
Kind regards,
Pieter Callewaert
From: Pieter Callewaert [mailto:pieter.callewaert@be-mobile.be] 
Sent: maandag 2 juli 2012 15:10
To: user@cassandra.apache.org
Subject: forceUserDefinedCompaction in 1.1.0
Hi guys,
We have a 6-node 1.0.9 cluster for production and 3-node 1.1.0 cluster for testing the new version of Cassandra.
In both we insert data in a particular CF with always a TTL of 31 days.
To clean up the files faster  we use the forceUserDefinedCompaction to manually force compaction on the old sstables which we are sure the data has expired.
In 1.0 this works perfect, but in the 1.1 the command executes without error, but in the log of the node I see the following:
INFO [CompactionExecutor:546] 2012-07-02 15:05:11,837 CompactionManager.java (line 337) Will not compact MapData024CTwT/MapData024CTwT-HOS-hc-21150: it is not an active sstable
INFO [CompactionExecutor:546] 2012-07-02 15:05:11,838 CompactionManager.java (line 350) No file to compact for user defined compaction
I am pretty sure the sstable because it should contain partly expired data en partly data which is still active.
Does this have to do something with the new directory structure from 1.1 ? Or are the parameters changed from the function?
Kind regards,
Pieter Callewaert