API for worker node retrieval of session request

• US 8,370,448 B2
• Filed: 12/28/2004
• Issued: 02/05/2013
• Est. Priority Date: 12/28/2004
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: SAP AG (SAP SE)
• Inventors: Galchev, Galin
• Primary Examiner(s): TODD, GREGORY G
• Application Number:
  US11/025,514
• Publication Number:
  US 20060143284A1
• Time in Patent Office: 2,961 Days
• Field of Search: 709213-216, 709226-229, 709/244, 719/312, 719328-329, 719/314, 719/318, 718/105
• US Class Current: 709/214
• CPC Class Codes: G06F 2209/5016 Session
• CPC Class Codes: G06F 2209/5018 Thread allocation
• CPC Class Codes: G06F 9/5033 considering data affinity
• CPC Class Codes: G06F 9/505 considering the load
• CPC Class Codes: G06F 9/544 Buffers; Shared memory; Pipes

Abstract

A method is described that involves, at a worker node, receiving a notification of a request from a queue. The notification contains a handle for a shared memory connection. The queue is implemented with a second shared memory connection. The method involves receiving the request from the shared memory through the connection. The method also involves generating a response to the request at the worker node and sending the response over the shared memory connection.

Claims

1. A method, comprising:

entering a notification of a request into a request notification queue, said notification including a handle of a connection to a request/response shared memory, said notification not including request data corresponding to said request, said request notification queue being dedicated to storing request notifications for a worker node, said request corresponding to a session;

entering said request data corresponding to said request into said request/response shared memory; and

based on said entering of said notification of said request and said entering of said request data, incrementing an active request counter in an entry of a session table, said entry corresponding to said session, said session table being stored in a session table shared memory.

2. The method of claim 1 wherein said request/response shared memory is configured to be shared by worker nodes of a standards-based software suite and worker nodes of a proprietary software suite.

3. The method of claim 1 wherein at least one of said entering of said notification of said request and said entering of said request data corresponding to said request includes using an instance of an object of an application program interface.

4. The method of claim 1, further comprising:

detecting a failure of said worker node;

extracting said notification of said request from said request notification queue;

decrementing said active request counter in said entry of said session table; and

based on said active request counter in said entry of said session table being equal to zero, submitting said notification of said request into an additional request notification queue, said additional request notification queue being dedicated to storing request notifications for an additional worker node.

5. The method of claim 4, further comprising selecting said additional worker node based on said additional request notification queue being empty and said additional worker node being assigned to handle said session.

6. The method of claim 4, further comprising, based on said active request counter in said entry of said session table being greater than zero, marking said session as corrupted.

7. The method of claim 1, wherein said connection to said request/response shared memory is implemented as an input/output stream across said request/response shared memory.

8. A non-transitory computer-readable storage medium having instructions embodied thereon, the instructions executable by a processor for performing a method, the method comprising:

entering a notification of a request into a request notification queue, said notification including a handle of a connection to a request/response shared memory, said notification not include request data corresponding to said request, said request notification queue being dedicated to store request notifications for a worker node, said request corresponding to said session;

entering said request data corresponding to said request into said request/response shared memory; and

based on said entering of said notification of said request and said entering of said request data, incrementing an active request counter in an entry of a session table, said entry corresponding to said session, said session table being stored in a session table shared memory.

9. The non-transitory computer-readable storage medium of claim 8 wherein said request/response shared memory is configured to be shared by worker nodes of a standards-based software suite and worker nodes of a proprietary software suite.

10. The non-transitory computer-readable storage medium of claim 8 wherein at least one of said entering of said notification of said request and said entering of said request data corresponding to said request includes using an instance of an object of an application program interface.

11. A system comprising:

at least one processor; and

a worker node implemented by the at least one processor and configured to;

retrieve a notification of a request from a request notification queue, the notification of the request including a handle for accessing a request/response shared memory and a data structure for accessing an entry of a shared session table in a session table shared memory, the entry corresponding to a session associated with the request, the notification of the request not including the request data, the request notification queue being dedicated to storing request notifications for the worker node;

use the handle to read request data corresponding to the request from the request/response shared memory;

process the request based on the request data;

use the handle to write response data to the request/response shared memory; and

use the data structure to decrement an active request count in the entry of the shared session table in the session table shared memory based on the writing of the response data to the request/response shared memory.

12. The system of claim 11, further comprising foreseeing that the worker node has an ability to process the request and wherein the retrieving of the notification of the request is based on the foreseeing.

13. The system of claim 11, wherein the worker node is further configured to:

determine the request corresponds to a distributable session; and

based on the determining, keep a session object corresponding to the worker node in a shared closure shared memory, the request/response shared memory being a first region of a shared memory, the shared closure shared memory being a second region of the shared memory, the shared memory being a memory resource accessible by a plurality of worker nodes, the plurality of worker nodes including the worker node.

14. The system of claim 11, wherein the notification of the request further includes a session key and the worker node is further configured to find the entry of the shared session table based on the session key.