Computer system and scale-up management method

A computer system comprising:

• a plurality of compute server;
• a plurality of storage servers;
• a plurality of execution units that are each respectively executed on one of the plurality of compute servers, wherein each execution unit executes a particular application that requires data to execute;
• and
• a management server which manages the plurality of compute servers and the plurality of storage servers to allocate the plurality of execution units among the plurality of compute servers, wherein the management server is configured to:
• determine that an additional instance of a particular execution unit is required to execute the particular application, and
• in response to determining that the additional instance of the particular execution unit is required:
• determine a particular logic unit that stores the data required for the particular application, wherein the particular logic unit is stored on a particular storage server among the plurality of storage servers,
• replicate the particular logic unit from the particular storage server to another storage server among the plurality of storage servers to form a replicated logic unit,
• create the additional instance of the particular execution unit on another compute server amongst the plurality of compute servers, and
• set the additional instance of the particular execution unit to refer to the replicated logic unit.