[
https://issues.apache.org/jira/browse/CASSANDRA-4781?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13485940#comment-13485940
]
Sylvain Lebresne commented on CASSANDRA-4781:
---------------------------------------------
Looks overall ok, but a few small remaining remarks:
* I'm good with making the "tombstone compaction interval" configurable but I
would have gone with a longer default one (say a day, or at least a few hours).
The tombstone compaction can be fairly improductive if we do them too often:
compacting a sstable for tombstones, even if you do collect tombstone, is kinda
bad if you're going to compact the sstable a short time later. In other words,
I don't think this interval is only useful for avoiding an infinite loop.
Besides, if it's configurable, the few people that have very heavy
delete/expiring workload can set that lower if that helps them.
* It's probably not worth exposing an interval in milliseconds, seconds would
be more than good enough. I also don't dislike putting the unit the option use
in the name too, so "tombstone_compaction_interval_seconds", though maybe it's
too long a name.
* Could be nice to validate the user input for the new option (should be > 0).
> Sometimes Cassandra starts compacting system-shema_columns cf repeatedly
> until the node is killed
> -------------------------------------------------------------------------------------------------
>
> Key: CASSANDRA-4781
> URL: https://issues.apache.org/jira/browse/CASSANDRA-4781
> Project: Cassandra
> Issue Type: Bug
> Affects Versions: 1.2.0 beta 1
> Environment: Ubuntu 12.04, single-node Cassandra cluster
> Reporter: Aleksey Yeschenko
> Assignee: Yuki Morishita
> Fix For: 1.2.0 beta 2
>
> Attachments: 4781.txt, 4781-v2.txt
>
>
> Cassandra starts flushing system-schema_columns cf in a seemingly infinite
> loop:
> INFO [CompactionExecutor:7] 2012-10-09 17:55:46,804 CompactionTask.java
> (line 239) Compacted to
> [/var/lib/cassandra/data/system/schema_columns/system-schema_columns-ia-32107-Data.db,].
> 3,827 to 3,827 (~100% of original) bytes for 3 keys at 0.202762MB/s. Time:
> 18ms.
> INFO [CompactionExecutor:7] 2012-10-09 17:55:46,804 CompactionTask.java
> (line 119) Compacting
> [SSTableReader(path='/var/lib/cassandra/data/system/schema_columns/system-schema_columns-ia-32107-Data.db')]
> INFO [CompactionExecutor:7] 2012-10-09 17:55:46,824 CompactionTask.java
> (line 239) Compacted to
> [/var/lib/cassandra/data/system/schema_columns/system-schema_columns-ia-32108-Data.db,].
> 3,827 to 3,827 (~100% of original) bytes for 3 keys at 0.182486MB/s. Time:
> 20ms.
> INFO [CompactionExecutor:7] 2012-10-09 17:55:46,825 CompactionTask.java
> (line 119) Compacting
> [SSTableReader(path='/var/lib/cassandra/data/system/schema_columns/system-schema_columns-ia-32108-Data.db')]
> INFO [CompactionExecutor:7] 2012-10-09 17:55:46,864 CompactionTask.java
> (line 239) Compacted to
> [/var/lib/cassandra/data/system/schema_columns/system-schema_columns-ia-32109-Data.db,].
> 3,827 to 3,827 (~100% of original) bytes for 3 keys at 0.096045MB/s. Time:
> 38ms.
> INFO [CompactionExecutor:7] 2012-10-09 17:55:46,864 CompactionTask.java
> (line 119) Compacting
> [SSTableReader(path='/var/lib/cassandra/data/system/schema_columns/system-schema_columns-ia-32109-Data.db')]
> INFO [CompactionExecutor:7] 2012-10-09 17:55:46,894 CompactionTask.java
> (line 239) Compacted to
> [/var/lib/cassandra/data/system/schema_columns/system-schema_columns-ia-32110-Data.db,].
> 3,827 to 3,827 (~100% of original) bytes for 3 keys at 0.121657MB/s. Time:
> 30ms.
> INFO [CompactionExecutor:7] 2012-10-09 17:55:46,894 CompactionTask.java
> (line 119) Compacting
> [SSTableReader(path='/var/lib/cassandra/data/system/schema_columns/system-schema_columns-ia-32110-Data.db')]
> INFO [CompactionExecutor:7] 2012-10-09 17:55:46,914 CompactionTask.java
> (line 239) Compacted to
> [/var/lib/cassandra/data/system/schema_columns/system-schema_columns-ia-32111-Data.db,].
> 3,827 to 3,827 (~100% of original) bytes for 3 keys at 0.202762MB/s. Time:
> 18ms.
> INFO [CompactionExecutor:7] 2012-10-09 17:55:46,914 CompactionTask.java
> (line 119) Compacting
> [SSTableReader(path='/var/lib/cassandra/data/system/schema_columns/system-schema_columns-ia-32111-Data.db')]
> .........
> Don't know what's causing it. Don't know a way to predictably trigger this
> behaviour. It just happens sometimes.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
