[
https://issues.apache.org/jira/browse/CASSANDRA-9120?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14494806#comment-14494806
]
Vladimir commented on CASSANDRA-9120:
-------------------------------------
If there is no way to add checksum, I'd try some simple: - create some status
file that indicates that we are trying to load cache file, delete it if loaded
successfully or failed by some reason that isn't OutOfMemory. Try to read that
file at next run and ignore cache. It's still fine to use
estimateMemorySizeForKeys as well but this isn't reliable as you mentioned and
can be useless.
> OutOfMemoryError when read auto-saved cache (probably broken)
> -------------------------------------------------------------
>
> Key: CASSANDRA-9120
> URL: https://issues.apache.org/jira/browse/CASSANDRA-9120
> Project: Cassandra
> Issue Type: Bug
> Environment: Linux
> Reporter: Vladimir
> Fix For: 3.0, 2.0.15, 2.1.5
>
>
> Found during tests on a 100 nodes cluster. After restart I found that one
> node constantly crashes with OutOfMemory Exception. I guess that auto-saved
> cache was corrupted and Cassandra can't recognize it. I see that similar
> issues was already fixed (when negative size of some structure was read).
> Does auto-saved cache have checksum? it'd help to reject corrupted cache at
> the very beginning.
> As far as I can see current code still have that problem. Stack trace is:
> {code}
> INFO [main] 2015-03-28 01:04:13,503 AutoSavingCache.java (line 114) reading
> saved cache
> /storage/core/loginsight/cidata/cassandra/saved_caches/system-sstable_activity-KeyCache-b.db
> ERROR [main] 2015-03-28 01:04:14,718 CassandraDaemon.java (line 513)
> Exception encountered during startup
> java.lang.OutOfMemoryError: Java heap space
> at java.util.ArrayList.<init>(Unknown Source)
> at
> org.apache.cassandra.db.RowIndexEntry$Serializer.deserialize(RowIndexEntry.java:120)
> at
> org.apache.cassandra.service.CacheService$KeyCacheSerializer.deserialize(CacheService.java:365)
> at
> org.apache.cassandra.cache.AutoSavingCache.loadSaved(AutoSavingCache.java:119)
> at
> org.apache.cassandra.db.ColumnFamilyStore.<init>(ColumnFamilyStore.java:262)
> at
> org.apache.cassandra.db.ColumnFamilyStore.createColumnFamilyStore(ColumnFamilyStore.java:421)
> at
> org.apache.cassandra.db.ColumnFamilyStore.createColumnFamilyStore(ColumnFamilyStore.java:392)
> at org.apache.cassandra.db.Keyspace.initCf(Keyspace.java:315)
> at org.apache.cassandra.db.Keyspace.<init>(Keyspace.java:272)
> at org.apache.cassandra.db.Keyspace.open(Keyspace.java:114)
> at org.apache.cassandra.db.Keyspace.open(Keyspace.java:92)
> at
> org.apache.cassandra.db.SystemKeyspace.checkHealth(SystemKeyspace.java:536)
> at
> org.apache.cassandra.service.CassandraDaemon.setup(CassandraDaemon.java:261)
> at
> org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:496)
> at
> org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:585)
> {code}
> I looked at source code of Cassandra and see:
> http://grepcode.com/file/repo1.maven.org/maven2/org.apache.cassandra/cassandra-all/2.0.10/org/apache/cassandra/db/RowIndexEntry.java
> 119 int entries = in.readInt();
> 120 List<IndexHelper.IndexInfo> columnsIndex = new
> ArrayList<IndexHelper.IndexInfo>(entries);
> It seems that value entries is invalid (negative) and it tries too allocate
> an array with huge initial capacity and hits OOM. I have deleted saved_cache
> directory and was able to start node correctly. We should expect that it may
> happen in real world. Cassandra should be able to skip incorrect cached data
> and run.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
