Re: XTM & parallel search

We have to add three more functions to eXtensible Transaction Manager API (XTM):

    /*
     * Calculate transaction state size. This method is invoked by EstimateTransactionStateSpace to copy transaction
     * state to parallel workers
     */
    size_t      (*GetTransactionStateSize)(void);

    /*
     * Serialize transaction state
     */
    void        (*SerializeTransactionState)(void* ctx);

    /*
     * Deserialize transaction state
     */
    void        (*DeserializeTransactionState)(void* ctx);