# US 2014/0195688 A1 · Token-based flow control of messages in a parallel computer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0195688 A1 - Document ID: US20140195688A1 - Status: Published application - Kind: A1 - Application number: 13/738,657 - Filed: 2013-01-10 - Published: 2014-07-10 - Earliest claimed: 2013-01-10 - Assignees: International Business Machines Corporation - Inventors: Charles J. ARCHER; James E. CAREY; Philip J. SANDERS; Brian E. SMITH - Web page: https://patentgrep.com/patent/US20140195688A1 ## CPC - H04L 67/1012: based on compliance of requirements or conditions with available server resources - H04L 47/215: using token-bucket - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Token-based flow control of messages in a parallel computer, the parallel computer including a plurality of compute nodes, each compute node including one or more computer processors, including: allocating, by a token administration module to a plurality of the computer processors in the parallel computer, a number of data communications tokens; identifying all communicators executing on each computer processor, where each communicator is participating in a distinct parallel operation executing on the parallel computer; allocating, to the communicators, the data communications tokens; determining, by a communicator attempting to send data to the destination, whether the communicator has enough available data communications tokens to send the data to the destination; and responsive to determining that the communicator has enough available data communications tokens to send the data, sending, by the communicator, the data to the destination. ## Claims ### Claim at position 1 1-7. (canceled) ### Claim 8 An apparatus for token-based flow control of messages in a parallel computer executing a plurality of parallel operations, the parallel computer including a plurality of compute nodes, each compute node including one or more computer processors, the apparatus comprising a computer memory operatively coupled to the one or more computer processors, the computer memory having disposed within it computer program instructions that, when executed by the one or more computer processors, cause the apparatus to carry out the steps of: allocating, by a token administration module to a plurality of the computer processors in the parallel computer, a number of data communications tokens, wherein: each data communications token represents an amount of data that a computer processor may send to a destination; and the number of data communications tokens allocated to each computer processor is determined in dependence upon token distribution rules; identifying, by the token administration module for each computer processor, all communicators executing on the computer processor, wherein each communicator is participating in a distinct parallel operation executing on the parallel computer; allocating, by the token administration module to the communicators, the data communications tokens; determining, by a communicator attempting to send data to the destination, whether the communicator has enough available data communications tokens to send the data to the destination; and responsive to determining that the communicator has enough available data communications tokens to send the data, sending, by the communicator, the data to the destination. ### Claim 9 (depends on 8) The apparatus of claim 8 further comprising computer program instructions that, when executed by the computer processor, cause the apparatus to carry out the step of, responsive to determining that the communicator does not have enough available data communications tokens to send the data to the destination, requesting, by the communicator to an additional communicator executing on the computer processor, additional data communications tokens. ### Claim 10 (depends on 9) The apparatus of claim 9 further comprising computer program instructions that, when executed by the computer processor, cause the apparatus to carry out the step of receiving, by the communicator, additional data communications tokens. ### Claim 11 (depends on 10) The apparatus of claim 10 further comprising computer program instructions that, when executed by the computer processor, cause the apparatus to carry out the step of returning, from the communicator to the additional communicator, the additional data communications tokens. ### Claim 12 (depends on 10) The apparatus of claim 10 further comprising computer program instructions that, when executed by the computer processor, cause the apparatus to carry out the step of returning, from the communicator to the token administration module, the additional data communications tokens. ### Claim 13 (depends on 8) The apparatus of claim 8 wherein allocating the data communications tokens further comprises allocating the data communications tokens in dependence upon token allocation rules. ### Claim 14 (depends on 8) The apparatus of claim 8 further comprising computer program instructions that, when executed by the computer processor, cause the apparatus to carry out the step of maintaining, by each communicator executing on the computer processor, a list of candidate communicators executing on the computer processor that have available data communications tokens. ### Claim 15 A computer program product for token-based flow control of messages in a parallel computer executing a plurality of parallel operations, the parallel computer including a plurality of compute nodes, each compute node including one or more computer processors, the computer program product disposed upon a computer readable medium, the computer program product comprising computer program instructions that, when executed, cause a computer to carry out the steps of: allocating, by a token administration module to a plurality of the computer processors in the parallel computer, a number of data communications tokens, wherein: each data communications token represents an amount of data that a computer processor may send to a destination; and the number of data communications tokens allocated to each computer processor is determined in dependence upon token distribution rules; identifying, by the token administration module for each computer processor, all communicators executing on the computer processor, wherein each communicator is participating in a distinct parallel operation executing on the parallel computer; allocating, by the token administration module to the communicators, the data communications tokens; determining, by a communicator attempting to send data to the destination, whether the communicator has enough available data communications tokens to send the data to the destination; and responsive to determining that the communicator has enough available data communications tokens to send the data, sending, by the communicator, the data to the destination. ### Claim 16 (depends on 15) The computer program product of claim 15 further comprising computer program instructions that, when executed, cause the computer to carry out the step of, responsive to determining that the communicator does not have enough available data communications tokens to send the data to the destination, requesting, by the communicator to an additional communicator executing on the computer processor, additional data communications tokens. ### Claim 17 (depends on 16) The computer program product of claim 16 further comprising computer program instructions that, when executed, cause the computer to carry out the step of receiving, by the communicator, additional data communications tokens. ### Claim 18 (depends on 17) The computer program product of claim 17 further comprising computer program instructions that, when executed, cause the computer to carry out the step of returning, from the communicator to the additional communicator, the additional data communications tokens. ### Claim 19 (depends on 17) The computer program product of claim 17 further comprising computer program instructions that, when executed, cause the computer to carry out the step of returning, from the communicator to the token administration module, the additional data communications tokens. ### Claim 20 (depends on 15) The computer program product of claim 15 wherein allocating the data communications tokens further comprises allocating the data communications tokens in dependence upon token allocation rules. ### Claim 21 (depends on 15) The computer program product of claim 15 further comprising computer program instructions that, when executed, cause the computer to carry out the step of maintaining, by each communicator executing on the computer processor, a list of candidate communicators executing on the computer processor that have available data communications tokens. ### Claim 22 (depends on 15) The computer program product of claim 15 wherein the computer readable medium comprises a signal medium. ### Claim 23 (depends on 15) The computer program product of claim 15 wherein the computer readable medium comprises a storage medium.