Methods and apparatus for avoidance of remote display packet buffer overflow

• US 7,269,136 B2
• Filed: 08/30/2002
• Issued: 09/11/2007
• Est. Priority Date: 08/30/2002
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Peacock, John Kent
• Primary Examiner(s): Jung; Min
• Application Number:
  US10/232,995
• Publication Number:
  US 20040042476A1
• Time in Patent Office: 1,838 Days
• Field of Search: 370/412, 370/229, 709/201, 709/202, 709/203
• US Class Current: 370/229
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 43/16 Threshold monitoring

Abstract

The present invention manages memory buffers in a computer network system. In one embodiment, a managing system on a thin client unit modifies an amount of central processing unit (CPU) resource on the thin client unit that is granted to a server application (e.g., a X server application). The modification is based on a function of how many network information packets are in a packet queue of the thin client unit. By dropping the amount of CPU resource granted lower and lower as the queue gets more and more full, the server application reduces the rate at which it sends commands, thus giving the thin client unit the opportunity to catch up in processing the commands already in the queue. When the number of packets in the queue passes a high critical threshold, the granted CPU resource is dropped to zero, effectively shutting off the server application. Accordingly, the above embodiment makes sure that the thin client unit is kept as busy as possible because the throttling of the granted CPU resource occurs only when there is an overabundance of work waiting to be done, and the embodiment avoids packet queue overflow by slowing down and eventually stopping the flow of packets from the server application to the thin client unit.

Claims

1. A computer network system for managing memory buffers comprising:

a network;

a first module for receiving a data packet from the network;

a second module for transmitting the data packet to the first module over the network;

a processor connected with the first module and having an amount of resource for processing the data packet;

a memory device associated with the first module and having an amount of space available for storing data packets before processing by the processor; and

a managing system associated with the memory device,

wherein the managing system allocates the amount of resource for processing the data packet, and

wherein the managing system is capable of determining the amount of resource for processing the data packet by monitoring the amount of space available for storing data packets.

2. The computer network system of claim 1, where the managing system allocates the amount of resource for processing the data packet in proportion to the amount of space available for storing data packets.

3. The computer network of claim 1, wherein the managing system uses a plurality of predetermined threshold levels on the amount of space available for storing data packets to determine the amount of resource for processing the data packet.

4. The computer network of claim 1, wherein the amount of resource for processing the data packet is measured in percentage and wherein the amount of resource for processing the data packet is approximately zero percent when the amount of space available for storing data packets is greater than approximately 15/16^th full.

5. The computer network system of claim 1, wherein the amount of resource for processing the data packet is measured in percentage and wherein the amount of resource for processing the data packet is approximately 100 percent when the amount of space available for storing data packets is not greater than approximately ½

^th full.

6. The computer network system of claim 1, wherein the amount of resource for processing the data packet allocated by the managing system is below a fair share of resource available on the processor for processing the data packet.

7. The computer network system of claim 1, wherein the management system includes a computer firmware located with the first module.

8. The computer network system of claim 1, wherein the first module includes a thin client and wherein the second module includes a server computer.

9. The computer network system of claim 1, wherein the second module includes a server application that is capable of generating the data packet.

10. The computer network system of claim 9, wherein the data packet includes a graphics primitive.

11. The computer network system of claim 10, wherein the second module further includes a client application, where the client application sends a protocol command to the server application, and wherein the graphics primitive is generated from the protocol command.

12. The computer network system of claim 11, wherein the protocol command includes an X protocol command.

13. The computer network system of claim 11, wherein the second module further includes a first server computer and a second server computer, wherein the client application is running on the first server computer, and wherein the server application is running on the second server computer.

14. The computer network system of claim 10, wherein the first module includes a graphics device and wherein the graphics primitive is in a format suitable for the graphics device.

15. A method for managing memory buffers in a computer network system comprising:

monitoring an amount of storage space available on a first module;

allocating a percentage of available resource on the first module for processing graphics information from a second module based on the monitored amount of storage space;

transmitting the allocated percentage to the second module over a network; and

limiting an amount of graphics information sent from the second module over the network to the first module based on the allocated percentage.

16. The method of claim 15, wherein allocating a percentage of available resource on the first module includes:

allocating a first percent of available resource on the first module for processing graphics information from the second module, if the amount of storage space available is greater than a first predetermined value full; and

allocating a second percent of available resource on the first module for processing graphics information from the second module, if the amount of storage available is not greater than a second predetermined value full,

wherein the first predetermined value is greater than the second predetermined value, and

wherein the first percent is less than the second percent.

17. The method of claim 16, wherein the first predetermined value is approximately 15/16^th and the second predetermined value is approximately ½

^th.

18. The method of claim 17, wherein the first percent is approximately zero and wherein the second percent is approximately 100.

19. The method of claim 18, wherein allocating a percentage of available resource on the first module further includes:

allocating approximately 25 percent of available resource on the first module for processing graphics information from the second module, if the amount of storage space available is not greater than approximately 15/16^th full and is greater than approximately ⅞

^th full;

allocating approximately 50 percent of available resource on the first module for processing graphics information from the second module, if the amount of storage available is not greater than approximately ⅞

^th full and is greater than ¾

^th full; and

allocating approximately 75 percent of available resource on the first module for processing graphics information from the second module, if the amount of storage available is not greater than approximately ¾

^th full and is greater than ½

^th full.

20. A computer network system for managing memory buffers comprising:

a network;

a first module for receiving graphics information from the network, the first module including an amount of space for storing the graphics information before processing by the processor, wherein the amount of resource for processing the graphics information is based on the amount of space for storing the graphics information;

a second module for transmitting the graphics information to the first module over the network;

a processor connected with the first module and having an amount of resource for processing the graphics information; and

a managing system associated with the first module;

wherein the managing system allocates the amount of resource for processing the graphics information, and

wherein the second module determines an amount of graphics information to be transmitted to the first module based on the amount of resource for processing the graphics information.