if another thread is reading x in a separate atomic section, it must get the old value of x = 10 if the transaction hasn't been committed yet.

Does having a write buffer mean there are limits to how many data we write in a transaction?

how does data versioning relate to conflict detection? in our midterm we had eager, pessimistic policy vs lazy, optimistic policy - is it always the case that lazy data versioning is used with optimistic policy? Since we're writing to memory immediately with eager data versioning, would pessimistic be better? (because we check for conflicts immediately)

@spendharkar, yes. eager data versioning is paired with pessimistic policy to guarantee isolation.