LeveledCompactionStrategy is too complacent
-------------------------------------------
Key: CASSANDRA-3224
URL: https://issues.apache.org/jira/browse/CASSANDRA-3224
Project: Cassandra
Issue Type: Bug
Components: Core
Affects Versions: 1.0.0
Reporter: Brandon Williams
Assignee: Benjamin Coverston
Fix For: 1.0.0
As the title, it barely does anything. I inserted 50G worth of data with 1G
heap and 99% overwrite ratio, and it only compacted twice:
{noformat}
INFO [CompactionExecutor:1] 2011-09-16 22:29:58,606 CompactionTask.java (line
220) Compacted to
[/var/lib/cassandra/data/Keyspace1/Standard1-h-2-Data.db,/var/lib/cassandra/data/Keyspace1/Standard1-h-4-Data.db,/var/lib/cassandra/data/Keyspace1/Standard1-h-5-Data.db,].
12,595,811 to 12,595,811 (~100% of original) bytes for 40,501 keys at
3.058122MBPS. Time: 3,928ms.
INFO [CompactionExecutor:1] 2011-09-16 22:29:58,607 CompactionTask.java (line
222) CF Total Bytes Compacted: 12,595,811
INFO [CompactionExecutor:3] 2011-09-16 22:29:58,889 CompactionTask.java (line
118) Compacting
[SSTableReader(path='/var/lib/cassandra/data/Keyspace1/Standard1-h-4-Data.db'),
SSTableReader(path='/var/lib/cassandra/data/Keyspace1/Standard1-h-2-Data.db'),
SSTableReader(path='/var/lib/cassandra/data/Keyspace1/Standard1-h-5-Data.db'),
SSTableReader(path='/var/lib/cassandra/data/Keyspace1/Standard1-h-3-Data.db')]
INFO [CompactionExecutor:3] 2011-09-16 22:30:06,900 CompactionTask.java (line
220) Compacted to
[/var/lib/cassandra/data/Keyspace1/Standard1-h-7-Data.db,/var/lib/cassandra/data/Keyspace1/Standard1-h-9-Data.db,/var/lib/cassandra/data/Keyspace1/Standard1-h-11-Data.db,/var/lib/cassandra/data/Keyspace1/Standard1-h-12-Data.db,/var/lib/cassandra/data/Keyspace1/Standard1-h-14-Data.db,/var/lib/cassandra/data/Keyspace1/Standard1-h-15-Data.db,].
28,374,396 to 28,374,396 (~100% of original) bytes for 91,236 keys at
3.380379MBPS. Time: 8,005ms.
INFO [CompactionExecutor:3] 2011-09-16 22:30:06,901 CompactionTask.java (line
222) CF Total Bytes Compacted: 40,970,207
{noformat}
Resulting in the following levels:
{noformat}
L0: 4965
L1: 6
L2: 0
L3: 0
L4: 0
L5: 0
L6: 0
L7: 0
{noformat}
This is obviously going to result in extremely poor read performance.
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira
