摘要 |
<p>A mechanism for replicating programs executing on a computer system having a first storage means is provided. The mechanism identifies the events corresponding to requests from one executing program, which may be different from the executing program to be replicated, which are non-deterministic and identifies the‘Non Abortable Events’(NAE's), which change irremediably the state of the external world that need to be reproduced in the replay of the programs. These events are immediately transferred for replay and the executing program is blocked until the transfer is acknowledged. For the other non-deterministic events, they are logged and sent to the executing program, the executing programs remaining blocked only if the log is full and/or if a timer between two NAEs expires, in this case a log transfer to the standby machine is performed to prepare replication before unblocking of the executing program.</p> |