What triggers a write-through/write-behind of entry processor changes?

What triggers a write-through/write-behind when a cache entry is modified by a custom entry processor (subclass of AbstractProcessor)? Is it simply the call to Entry.setValue() that triggers this or are entry modifications detected in some other way?
The reason I am asking is that in our Coherence cluster it looks like some entry modifications through entry processors have not triggered a write-behind, and I see no logical pattern as to which ones have and which ones haven't except that some specific entries are just never written to our database. We see from our logs that our implementation of the CacheStore.store() method is not called in these cases, and we also see that the cache entry has been modified successfully.
We are using Coherence 3.3 on a three machine cluster with 8 nodes on each machine, accessed from clients through a TCP extend proxy.
Mikael Carlstedt
mBlox Inc
Edited by: user3849225 on 16-Sep-2010 04:57

Hi Mikael
Calling setEntry() will result in a call to the CacheStore.store() method unless the value you are setting is the same as the existing entry value. If you are using writebehind then storeAll() will be called instead of store() if there are multiple entries waiting to be stored. Writebehind will also coelesce entries so that only the last entry for a given key will be stored.
What patch level are you using?
Edited by: pmackin on Sep 17, 2010 12:08 AM

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