Ah, here's the extended explanation about transactions :)

I would also rephrase this to make it clear that we would have to store the entries locally: This is because REPEATABLE_READ transactions have to keep track of all the entries they have read (which in this case would include the entries that did not match the filter). Keeping all the values on a single node would negate the benefits of using a filter and/or converter, and in many cases it would cause OutOfMemoryErrors.