Computer system, cache management method, and computer

A cache management method for a computer system including a server on which an application runs, and a storage system that stores data to be used by the application,

• the server including a first processor, a first memory coupled to the first processor, a cache memory system coupled to the first processor, for providing a plurality of cache areas for temporarily storing data, a connection interface coupled to the first processor, for establishing connection to the cache memory system, and a first network interface coupled to the first processor, for establishing connection to another apparatus,
• the storage system including a controller including a second processor, a second memory coupled to the second processor, and a second network interface coupled to the second processor, for establishing connection to another apparatus, and a plurality of storage apparatus coupled to the controller,
• the first memory storing a program for achieving an operating system that controls the server,
• the second memory storing a program for achieving a storage controller that controls the storage system,
• the operating system including a cache driver for controlling cache data, a cache memory system driver for controlling an I/O process for the cache memory system, and a storage system driver for controlling an I/O process for the storage system,
• the cache memory system driver having a plurality of first queues, each of the plurality of first queues registers at least one of I/O request for the cache memory system,
• the storage system driver having at least one second queue in which at least one of I/O request for the storage system is to be registered,
• a condition of each of the plurality of cache areas being configured so as to be switchable to any one of a first cache condition in which data is readable from a cache area and writing of data into the cache area is prohibited, a second cache condition in which reading of data from the cache area is prohibited and writing of data into the cache area is permitted, and a third cache condition in which reading of data from the cache area is prohibited and writing of data into the cache area is prohibited,
• the cache management method including:
• a first step of determining, by the cache driver, whether a condition of a first cache area for storing cache data of data to be stored in a first storage area in the storage system is the first cache condition in a case of receiving from the application an instruction to register a first write request to command writing of data into the first storage area;
• and
• a second step of changing, by the cache driver, the condition of the first cache area to the third cache condition from the first cache condition, in a case of determining that the condition of the first cache area is the first cache condition.

A computer on which an application runs, the computer comprising:

• a processor;
• a memory coupled to the processor;
• a cache memory system coupled to the processor;
• a connection interface coupled to the processor, for establishing connection to the cache memory system;
• and
• a network interface coupled to the processor, for establishing connection to another apparatus,
• the memory storing a program for achieving an operating system that controls the computer,
• the cache memory system including a plurality of cache areas for temporarily storing cache data of data to be stored in a storage system to be coupled to the computer,
• the operating system including:
• a cache driver for controlling the cache data;
• a cache memory system driver for controlling an I/O process for the cache memory system;
• and
• a storage system driver for controlling an I/O process for the storage system,
• the cache memory system driver having a plurality of queues, each of the plurality of first queues registers at least one of I/O request for the cache memory system,
• a condition of each of the plurality of cache areas being configured so as to be switchable to any one of a first cache condition in which data is readable from a cache area and writing of data into the cache area is prohibited, a second cache condition in which reading of data from the cache area is prohibited and writing of data into the cache area is permitted, and a third cache condition in which reading of data from the cache area is prohibited and writing of data into the cache area is prohibited,
• the cache driver being configured to:
• determine whether a condition of a first cache area for storing cache data of data to be stored in a first storage area in the storage system is the first cache condition in a case of receiving an instruction to register a first write request to command writing of data into the first storage area;
• and
• change the condition of the first cache area to the third cache condition from the first cache condition in a case of determining that the condition of the first cache area is in the first cache condition.