Process transparent multi storage mode data transfer and buffer control

• US 4,937,737 A
• Filed: 08/31/1988
• Issued: 06/26/1990
• Est. Priority Date: 06/17/1985
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Schwane, Walter H., Ziecina, Frederick J.
• Primary Examiner(s): CLARK, DAVID
• Application Number:
  US07/240,368
• Time in Patent Office: 664 Days
• Field of Search: 364/200, 364/900
• US Class Current: 719/310
• CPC Class Codes: G06F 15/161 Computing infrastructure, e.g. computer clusters, blade chassis or hardware partitioning casings, cabinets, racks or drawers for data centers H05K5/00
• CPC Class Codes: G06F 9/544 Buffers; Shared memory; Pipes
• CPC Class Codes: H04L 69/00 Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass networks security protocols H04L9/40; wireless communication networks H04W

Abstract

An interprocess communication facility in a processor system provides for communication of data between at least two processes. The facility supports a plurality of different data transfer modes which are provided by storage management services of the processor or processors. A process interface provides a common interface for each communicating process to select data transfer modes independently of the data transfer mode chosen by the other communicating process. A data access control function is coupled to the process interface and to the storage management services. The data access control function controls the use of the storage management services as a function of the transfer modes chosen by the communicating processes. It is transparent to the processes as to which transfer mode was chosen by each other.

Claims

1. An interprocess communication facility in a distributed processor system, at least one processor coupled to a storage device, and each processor having storage management services for controlling access to stored data, the interprocess communication facility providing a communication between at least two communicating processes, which are located at one or more processors, the facility supporting a plurality of different data transfer storage management modes, the selection of which is controlled by the processes, the facility at each processor comprising:

process interface means coupled to each communicating process for providing a common interface between communicating processes, said process interface means further including means for permitting each communicating process to utilize data transfer storage management modes independently of the data transfer storage management mode chosen by the other communicating process; and

data access control means communicatively coupled to this process interface means and the storage management services for controlling the storage management services as a function of the data transfer storage management modes chosen by the communicating processes.

2. The interprocess communication facility of claim 1 wherein a sending process having data to be sent which is stored in a first storage area associated therewith is communicating with a receiving process having a second storage area associated therewith and wherein the sending process selects a data transfer storage management mode without regard to whether it has access to the second storage area, and the receiving process selects a data transfer storage management mode without regard to whether it has access to the first storage area.

3. The interprocess communication facility of claim 2 wherein the sending process has management responsibility for the first storage area and the receiving process has management responsibility for the second storage area.

4. The interprocess communication facility of claim 3 wherein the data transfer storage management modes comprise:

freebuf mode wherein the data access control facility releases the sending process from management responsibility for a storage area; and

getbuf mode for obtaining management responsibility for a storage area; and

wherein each process comprises means for selecting data transfer storage management modes.

5. The interprocess communication facility of claim 4 wherein the selection of freebuf mode by the sending process causes storage management services to make a copy of the data in the first storage area, and the management responsibility for the first storage area to be transferred to a different process by the data access control means.

6. The interprocess communication facility of claim 4 wherein the selection of getbuf mode by the receiving process causes the data access control means to transfer management responsibility to the receiving process.

7. The interprocess communication facility of claim 4 wherein the selection of freebuf by the sending process and the selection of getbuf by the receiving process causes the data access control means to transfer management responsibility for the first storage area containing data to be transferred to the receiving process if the receiving process has access to the first storage area.

8. The interprocess communication facility of claim 7 wherein the data access control means transfers to the receiving process management responsibility for a storage area containing a copy of the data if the data is not in shared storage.

9. The interprocess communication facility of claim 2 wherein the data transfer storage management modes comprise:

move mode wherein the data access control means controls the storage management services to transfer a copy of the data to the communicating processes;

pass mode wherein the data access control means controls the storage management services to transfer the data to the process receiving the communication; and

locate mode wherein the data access control means controls the storage management services to transfer a pointer to the data when it is in shared storage and transfer a copy of the data when shared storage is not available.

10. The interprocess communication facility of claim 9 wherein each process comprises means for selecting a data transfer storage management mode, and wherein the selection of move mode by the means for selecting a data transfer storage management mode causes the data access control means to make a copy of the data in storage available to the receiving process regardless of the mode specified by the receiving process.

11. The interprocess communication facility of claim 9 wherein the selection of pass mode by the means for selecting a data transfer storage management mode causes the data access control means to make a copy of the data in storage available to the receiving process.

12. The interprocess communication facility of claim 9 wherein each process comprises means for selecting a data transfer storage management mode, and wherein the selection of locate mode by the means for selecting a data transfer storage management-mode in the sending process causes the receiving process to access the data directly if the data resides in storage accessible to the receiving process as determined by storage management services.

13. The interprocess communication facility of claim 12 wherein a copy of the data is made by storage management services in storage available to the receiving process if the data to be sent does not reside in storage accessible to the receiving process.

14. The interprocess communication facility of claim 12 wherein a copy of the data is made by storage management services in storage available to the receiving process if the receiving process does not specify locate mode to receive the data.

15. The interprocess communication facility of claim 1 wherein the data transfer storage management modes comprise:

freebuf mode wherein the data access control facility releases the sending process from management responsibility for a storage area; and

getbuf mode wherein the data access control facility assigns management responsibility for a storage area to the receiving process.

16. A process to process data transfer management facility in a multiprocess system comprising:

at least two communicating processes, each process having means for selecting its own data transfer storage management mode for use in communicating with another process;

storage means for providing storage areas for the data to be transferred, wherein each communicating process has means for accessing at least a portion of the storage means; and

storage management means coupled to the storage means and to the communicating processes for transferring data between storage areas in accordance with the data transfer storage management modes selected by the communicating processes such that each communicating process uses its selected data transfer storage management mode for transfer of data without regard to the data transfer storage management mode selected by any other process.

17. A method of transferring data between two communicating processes in a computer system which has at least one storage device, and storage management services, the method comprising the steps of:

(a) selecting a first data transfer storage management mode for a data sending process;

(b) selecting a second data transfer storage management mode for a data receiving process, wherein the selection of the second data transfer storage management mode is made without regard to the selection of the first data transfer storage management mode;

(c) determining if the data transfer storage management modes selected by each process will require storage management services in addition to storage management services normally required given the data transfer storage management mode selected by the data sending process;

(d) transferring the data between said processes on the computer using said data transfer storage management modes if no additional storage management services are required;

(e) determining storage management services required if the data transfer storage management modes require additional services; and

(f) executing on the computer system, the storage management services required transparent to each of said processes so that it appears to the processes as though data is transferred in accordance with their selected data transfer storage management modes.

18. A process to process data transfer management facility in a multiprocess system comprising:

at least two communicating processes;

storage means coupled to the communicating processes for providing storage areas for the data to be transferred, each communicating process having access to at least a portion of the storage means;

mode means in each communicating process for indicating the data transfer storage management mode in which the process attempts to transfer data;

data transfer means for providing data transfers; and

interface means coupled between the communicating processes and the data transfer means for controlling the data transfer means to transfer data in accordance with the data transfer storage management modes indicated by the mode means in each communicating process so that each communicating process communicates using its selected mode.