1. A method for reducing dedicated type-stable allocation pools using an unstable attribute, the method comprising: providing a mechanism enabling one of a plurality of transactions to safely examine a transaction data structure of another of the transactions; setting a thread unstable attribute for the transaction data structure before acquiring a pointer to the transaction data structure; clearing the thread unstable attribute when the pointer to the transaction data structure is no longer needed; and during a garbage collection pause, deleting objects in a type-stable allocation pool if the thread unstable attribute is not set on any of the threads.