You're right. Created CASSANDRA-5170 and attached a patch switching to ConcurrentHashMap.
On Thu, Jan 17, 2013 at 5:44 PM, Kirk True <k...@mustardgrain.com> wrote: > Hi all, > > > > A client is using Cassandra 1.2.0 (embedded) into their system. On > startup of one of the nodes in the system, they're seeing a > ConcurrentModificationException: > > > > java.util.ConcurrentModificationException > > at java.util.HashMap$HashIterator.nextEntry(HashMap.java:810) > > at java.util.HashMap$KeyIterator.next(HashMap.java:845) > > at > org.apache.cassandra.dht.BootStrapper.getBootstrapSource(BootStrapper.j > ava:146) > > at > org.apache.cassandra.dht.BootStrapper.getBalancedToken(BootStrapper.jav > a:135) > > at > org.apache.cassandra.dht.BootStrapper.getBootstrapTokens(BootStrapper.j > ava:115) > > at > org.apache.cassandra.service.StorageService.joinTokenRing(StorageServic > e.java:611) > > at > org.apache.cassandra.service.StorageService.initServer(StorageService.j > ava:499) > > at > org.apache.cassandra.service.StorageService.initServer(StorageService.j > ava:397) > > at > org.apache.cassandra.service.CassandraDaemon.setup(CassandraDaemon.java > :309) > > at > org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.j > ava:397) > > at CassandraServer.start(CassandraServer.java:415) > > > > LoadBroadcaster has an internal map named loadInfo that it both > modifies internally as well as makes available via an accessor method > (getLoadInfo). > > > > StorageService.joinTokenRing contains this line (611): > > > > tokens = BootStrapper.getBootstrapTokens(tokenMetadata, > LoadBroadcaster.instance.getLoadInfo()); > > > > So that's how BootStrapper gets access to LoadBroadcaster's loadInfo. > > > > There are a few places where LoadBroadcaster is called by Gossiper to > add and remove nodes which then modifies loadInfo. There's no logging > in many of those places, so it's hard to know which one it is. > > > > Should LoadBroadcaster.instance.getLoadInfo() return a copy of the > internal map rather than just a reference to it? > > > > Thanks, > > Kirk -- Jonathan Ellis Project Chair, Apache Cassandra co-founder, http://www.datastax.com @spyced
