Myron, Thank you for reporting the issue. The assertion happens when the value is present in the store, absent in the cache and you run invokeAll(). As a temporary solution, you can either call invoke() for each particular key individually, or call getAll() for the keys prior to calling invokeAll() (this will pre-load the values to the cache). Since the issue is pretty critical, I believe it will be fixed in 1.6 (if not earlier).
Yakov, Sam, I created a ticket [1] and suggested a fix there, can you take a look and check if the fix is ok? Thanks, AG [1] https://issues.apache.org/jira/browse/IGNITE-2645
