In a method and arrangement for exchanging data between a first processing unit, containing first status information about the first data processing unit, and a second data processing unit, containing second status information about the first data processing unit, data are exchanged between the first and second units during transactions that include a status-changing transaction, which can be of two different types. Upon a successful completion of the status-changing transaction, the first and second status information are revised so that they match. Upon an unsuccessful completion of the status-changing transaction, at least one of the first and second status information is set dependent on the type of the status-changing transaction.