[
https://issues.apache.org/jira/browse/CASSANDRA-4142?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Jonathan Ellis updated CASSANDRA-4142:
--------------------------------------
Attachment: 4142-v2.txt
v2 attached:
- Renames KeyScanner to o.a.c.db.compaction.ICompactionScanner
- Remove AbstractCompactionIterable.getScanners in favor of ACS.getScanners,
which wires it in to normal compactions as well. (This lets
ParallelCompactionIterator be more agressive about how much memory it lets each
scanner use, too.)
- Updated LCS.getScanners constructor to use a Multimap, which simplifies
things a bit.
> OOM Exception during repair session with LeveledCompactionStrategy
> ------------------------------------------------------------------
>
> Key: CASSANDRA-4142
> URL: https://issues.apache.org/jira/browse/CASSANDRA-4142
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Affects Versions: 1.0.0
> Environment: OS: Linux CentOs 6
> JDK: Java HotSpot(TM) 64-Bit Server VM (build 14.0-b16, mixed mode)
> Node configuration:
> Quad-core
> 10 GB RAM
> Xmx set to 2,5 GB (as computed by default).
> Reporter: Romain Hardouin
> Assignee: Sylvain Lebresne
> Fix For: 1.1.1
>
> Attachments: 4142-v2.txt, 4142.txt
>
>
> We encountered an OOM Exception on 2 nodes during repair session.
> Our CF are set up to use LeveledCompactionStrategy and SnappyCompressor.
> These two options used together maybe the key to the problem.
> Despite of setting XX:+HeapDumpOnOutOfMemoryError, no dump have been
> generated.
> Nonetheless a memory analysis on a live node doing a repair reveals an
> hotspot: an ArrayList of SSTableBoundedScanner which appears to contain as
> many objects as there are SSTables on disk.
> This ArrayList consumes 786 MB of the heap space for 5757 objects. Therefore
> each object is about 140 KB.
> Eclipse Memory Analyzer's denominator tree shows that 99% of a
> SSTableBoundedScanner object's memory is consumed by a
> CompressedRandomAccessReader which contains two big byte arrays.
> Cluster information:
> 9 nodes
> Each node handles 35 GB (RandomPartitioner)
> This JIRA was created following this discussion:
> http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Why-so-many-SSTables-td7453033.html
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
