How to set LeveledCompactionStrategy for an existing table

[Jean-Armel Luce]

Hello,

I am using Cassandra 1.1.1 and CQL3.
I have a cluster with 1 node (test environment)
Could you tell how to set the compaction strategy to Leveled Strategy for
an existing table ?

I have a table pns_credentials

jal@jal-VirtualBox:~/cassandra/apache-cassandra-1.1.1/bin$ ./cqlsh -3
Connected to Test Cluster at localhost:9160.
[cqlsh 2.2.0 | Cassandra 1.1.1 | CQL spec 3.0.0 | Thrift protocol 19.32.0]
Use HELP for help.
cqlsh> use test1;
cqlsh:test1> describe table pns_credentials;

CREATE TABLE pns_credentials (
  ise text PRIMARY KEY,
  isnew int,
  ts timestamp,
  mergestatus int,
  infranetaccount text,
  user_level int,
  msisdn bigint,
  mergeusertype int
) WITH
  comment='' AND
  comparator=text AND
  read_repair_chance=0.100000 AND
  gc_grace_seconds=864000 AND
  default_validation=text AND
  min_compaction_threshold=4 AND
  max_compaction_threshold=32 AND
  replicate_on_write='true' AND
  compaction_strategy_class='SizeTieredCompactionStrategy' AND
  compression_parameters:sstable_compression='SnappyCompressor';

I want to set the LeveledCompaction strategy for this table, so I execute
the following ALTER TABLE :

cqlsh:test1> alter table pns_credentials
         ... WITH compaction_strategy_class='LeveledCompactionStrategy'
         ... AND compaction_strategy_options:sstable_size_in_mb=10;

In Cassandra logs, I see some informations :
 INFO 10:23:52,532 Enqueuing flush of
Memtable-schema_columnfamilies@965212657(1391/1738 serialized/live bytes,
20 ops)
 INFO 10:23:52,533 Writing Memtable-schema_columnfamilies@965212657(1391/1738
serialized/live bytes, 20 ops)
 INFO 10:23:52,629 Completed flushing
/var/lib/cassandra/data/system/schema_columnfamilies/system-schema_columnfamilies-hd-94-Data.db
(1442 bytes) for commitlog position ReplayPosition(segmentId=3556583843054,
position=1987)


However, when I look at the description of the table, the table is still
with the SizeTieredCompactionStrategy
cqlsh:test1> describe table pns_credentials ;

CREATE TABLE pns_credentials (
  ise text PRIMARY KEY,
  isnew int,
  ts timestamp,
  mergestatus int,
  infranetaccount text,
  user_level int,
  msisdn bigint,
  mergeusertype int
) WITH
  comment='' AND
  comparator=text AND
  read_repair_chance=0.100000 AND
  gc_grace_seconds=864000 AND
  default_validation=text AND
  min_compaction_threshold=4 AND
  max_compaction_threshold=32 AND
  replicate_on_write='true' AND
  compaction_strategy_class='SizeTieredCompactionStrategy' AND
  compression_parameters:sstable_compression='SnappyCompressor';

In the schema_columnfamilies table (in system keyspace), the table
pns_credentials is still using the SizeTieredCompactionStrategy
cqlsh:test1> use system;
cqlsh:system> select * from schema_columnfamilies ;
...
         test1 |   pns_credentials |                   null | KEYS_ONLY
|                        [] |         |
org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy
|                          {}
|
org.apache.cassandra.db.marshal.UTF8Type |
{"sstable_compression":"org.apache.cassandra.io.compress.SnappyCompressor"}
|          org.apache.cassandra.db.marshal.UTF8Type |           864000 |
1029 |       ise |     org.apache.cassandra.db.marshal.UTF8Type
|                        0 |                       32
|                        4 |                0.1 |               True
|          null | Standard |        null
...


I stopped/started the Cassandra node, but the table is still with
SizeTieredCompactionStrategy

I tried using cassandra-cli, but the alter is still unsuccessfull.

Is there anything I am missing ?


Thanks.

Jean-Armel