VIRTUAL MACHINES FAILOVER

摘要

Disclosed is a computer system (100) comprising a processor unit (110) adapted to run a virtual machine in a first operating mode; a cache (120) accessible to the processor unit, said cache comprising a plurality of cache rows (1210), each cache row comprising a cache line (1214) and an image modification flag (1217) indicating a modification of said cache line caused by the running of the virtual machine; and a memory (140) accessible to the cache controller for storing an image of said virtual machine; wherein the processor unit comprises a replication manager adapted to define a log (200) in the memory prior to running the virtual machine in said first operating mode; and said cache further includes a cache controller (122) adapted to periodically check said image modification flags; write only the memory address of the flagged cache lines in the defined log and subsequently clear the image modification flags. A computer cluster including such computer systems and a method of managing such a computer cluster are also disclosed.

主权项

1. A method of operating a computer cluster including a first computer system including a memory storing an image of a virtual machine, at least one processor unit adapted to run the virtual machine in a first operation mode, and a cache accessible to the at least one processor unit, said cache including, for each of a plurality cache lines, a respective associated one of a plurality of image modification flags indicating modification of the associated cache line caused by the running of the virtual machine, the method comprising:
in the first operation mode, a processor unit of the first computer system:
defining a log in the memory of the first computer system;running the virtual machine using said image;upon modifying a cache line of the cache during said running step, signaling modification of the cache line by setting the associated image modification flag; and the processor unit additionally:
writing the memory addresses only of cache lines indicated as modified by the plurality of image modification flags to said defined log; and
clearing the plurality of image modification flags.