Hello, Kamil! Could you please provide your cache configuration?
Kind regards, Semyon. 17.05.2021, 09:10, "kimec.ethome.sk" <ki...@ethome.sk>: > Greetings, > > we have recently run into a concurrency issue in an entry processor. > > Suppose we have a cache that is IgniteCache<Long, HashMap<String, > String>>. > Entries in this cache are added and modified solely via EntryProcessors. > > Now suppose that the cache contains a value for key 1L - a map with > several key value pairs. > Next suppose, we execute the same entry processor for the key 1L TWICE > at the very same time on the same value. > > Up until now my understanding was that since the HashMap is stored > offheap, each entry processor would get it's own deserialized copy of > the HashMap for modification and Ignite would then orchestrate the > update of the value (serializing/deserializing the value to offheap > reagion). > > However, what we see in our test case is that both entry processor > "executions" receive the same deserialized HashMap and thus the > modification of the HashMap in both processors at the same time causes > java.util.ConcurrentModificationException. > > I would expect this kind of behaviour in case the HashMap was stored on > regular Java heap but if the value is deserialized from offheap region? > Is my logic correct? I am trying to wrap my head around this but does > this mean that any complex datastractures stored in must require > separate locking? > > Thanks! > > Kamil
