Patent application number | Description | Published |
20090210559 | PROCESSING A VARIABLE LENGTH DEVICE COMMAND WORD AT A CONTROL UNIT IN AN I/O PROCESSING SYSTEM - A computer program product, apparatus and method for processing a variable length device command word (DCW) at a control unit configured for communication with an input/output (I/O) subsystem in an I/O processing system. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes receiving a DCW at the control unit from the I/O subsystem. The DCW specifies one or more I/O operations and includes a command, a control data count, and control data having a varying length specified by the control data count. The control data is extracted in response to the control data count. The command is then executed in response to the extracted control data to perform the specified one or more I/O operations. | 08-20-2009 |
20090210560 | CANCEL INSTRUCTION AND COMMAND FOR DETERMINING THE STATE OF AN I/O OPERATION - The state of an input/output (I/O) operation is determined in an I/O processing system. A command is received from an I/O operating system at a channel subsystem for initiating the I/O operation, a time period is for completion of the I/O operation, and the command for initiating the I/O operation is sent from the channel subsystem to the control unit. Responsive to the time period nearing elapsing without the I/O operation completing, a cancel instruction is received from the I/O operating system at the channel subsystem. Responsive to a determination by the I/O operating system to interrogate the control unit, an instruction to interrogate the control unit is received with the cancel instruction from the I/O operating system. | 08-20-2009 |
20090210563 | PROVIDING INDIRECT DATA ADDRESSING FOR A CONTROL BLOCK AT A CHANNEL SUBSYSTEM OF AN I/O PROCESSING SYSTEM - An computer program product, apparatus, and method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes the host computer system obtaining a transport command word (TCW) for an I/O operation. The TCW specifies a location of one or more I/O commands and a flag. The flag is set to indicate that the location is an indirect address. The host computer system extracts the location of the one or more I/O commands and the flag from the TCW. The host computer system gathers the one or more I/O commands responsive to the location specified by the TCW and the flag, and then forwards the one or more I/O commands to the control unit for execution. | 08-20-2009 |
20090210572 | COMPUTER COMMAND AND RESPONSE FOR DETERMINING THE STATE OF AN I/O OPERATION - A computer program product, apparatus, and method are provided for determining a state of an input/output (I/O) operation in an I/O processing system. A request from a channel subsystem is received at a control unit for performing the I/O operation. After a predetermined amount of time passes without the I/O operation completing, an interrogation request is received from the channel subsystem at the control unit for determining the state of the I/O operation. A response is sent from the control unit to the channel subsystem indicating the state of the I/O operation in response to the interrogation request. The response also includes information regarding a state of an I/O device executing the I/O operation and information indicating a state of the control unit controlling the I/O device executing the I/O operation. | 08-20-2009 |
20090210573 | COMPUTER COMMAND AND RESPONSE FOR DETERMINING THE STATE OF AN I/O OPERATION - A state of an input/output (I/O) operation in an I/O processing system is determined. A request for performing the I/O operation is received from an I/O operating system at a channel subsystem and forwarded to a control unit controlling an I/O device for executing the I/O operation. After a predetermined amount of time passes without receiving indication from the control unit that the I/O operation is completed, an interrogation request is received at the channel subsystem from the I/O operating system for determining the state of the I/O operation. An interrogation command is sent from the channel subsystem to the control unit. A response is received from the control unit, the response indicates a state of the I/O device executing the I/O operation, a state of the control unit controlling the I/O device executing the I/O operation, and the state of the I/O operation being executed. | 08-20-2009 |
20090210576 | PROVIDING INDIRECT DATA ADDRESSING IN AN INPUT/OUTPUT PROCESSING SYSTEM WHERE THE INDIRECT DATA ADDRESS LIST IS NON-CONTIGUOUS - Systems, methods and computer program products for providing indirect data addressing at an I/O subsystem of an I/O processing system. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes receiving a control word for an I/O operation. The control word includes an indirect data address for data associated with the I/O operation. The indirect data address includes a starting location of a list of storage addresses that collectively specify the data, the list spans two or more non-contiguous storage locations. Data is gathered responsive to the list. The gathered data is transmitted to a control unit in the I/O processing system. | 08-20-2009 |
20090210581 | BI-DIRECTIONAL DATA TRANSFER WITHIN A SINGLE I/O OPERATION - An article of manufacture, apparatus, and a method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The method includes the host computer system obtaining a transport command word (TCW) for an I/O operation having both input and output data. The TCW specifies a location of the output data and a location for storing the input data. The host computer system forwards the I/O operation to the control unit for execution. The host computer system gathers the output data responsive to the location of the output data specified by the TCW, and then forwards the output data to the control unit for use in the execution of the I/O operation. The host computer system receives the input data from the control unit and stores the input data at the location specified by the TCW. | 08-20-2009 |
20110131343 | PROVIDING INDIRECT DATA ADDRESSING IN AN INPUT/OUTPUT PROCESSING SYSTEM WHERE THE INDIRECT DATA ADDRESS LIST IS NON-CONTIGUOUS - Systems, methods and computer program products for providing indirect data addressing at an I/O subsystem of an I/O processing system. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes receiving a control word for an I/O operation. The control word includes an indirect data address for data associated with the I/O operation. The indirect data address includes a starting location of a list of storage addresses that collectively specify the data, the list spans two or more non-contiguous storage locations. Data is gathered responsive to the list. The gathered data is transmitted to a control unit in the I/O processing system. | 06-02-2011 |
20110196993 | BI-DIRECTIONAL DATA TRANSFER WITHIN A SINGLE I/O OPERATION - An article of manufacture, apparatus, and a method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The method includes the host computer system obtaining a transport command word (TCW) for an I/O operation having both input and output data. The TCW specifies a location of the output data and a location for storing the input data. The host computer system forwards the I/O operation to the control unit for execution. The host computer system gathers the output data responsive to the location of the output data specified by the TCW, and then forwards the output data to the control unit for use in the execution of the I/O operation. The host computer system receives the input data from the control unit and stores the input data at the location specified by the TCW. | 08-11-2011 |
20110320602 | DISCOVERY OF LOGICAL IMAGES AT STORAGE AREA NETWORK ENDPOINTS - A method for detecting virtual images in a network, the network including a host system and a plurality of physical devices in operable communication with one another, includes forming a query packet at the host system; providing the query packet to at least one of the plurality of physical devices; forming at the at least of the plurality of physical devices a first vector in response to the query packet, the first vector including a bit for each possible virtual image that may be formed in the at least one of the plurality of devices and indicating which of the virtual images are configured and addressable; and providing the first vector to the host system. | 12-29-2011 |
20110320640 | DISCOVERY AND CONFIGURATION OF DEVICE CONFIGURATIONS - A computer program product for processing communications between a host processor and a plurality of devices includes a tangible storage medium for performing a method comprising: receiving, by the host processor, physical configuration information including identification of a location of each physical endpoint connected to the host processor and a plurality of communication paths associated with each physical endpoint; sending at least one message to each physical endpoint on each of the plurality of communication paths, the at least one message requesting identification of a logical entity at the endpoint, and receiving logical configuration information identifying the logical entity; and generating a data collection accessible by the host processor, the data collection including the physical configuration information and the logical configuration information for each logical entity, and identification of a location of each physical endpoint connected to the host processor and a plurality of communication paths to each logical entity. | 12-29-2011 |
20120017121 | MONITORING NETWORK PERFORMANCE AND DETECTING NETWORK FAULTS USING ROUND TRIP TRANSMISSION TIMES - A computer program product is provided for performing a method including: receiving transmission data over a selected time interval for each of a plurality of communication paths; calculating an average round-trip transmission time for each of the plurality of communication paths over the time interval; comparing an average round-trip transmission time for a communication path having the highest average round-trip transmission time to a threshold value and to a multiple of an average round-trip transmission time for a communication path having the lowest average round-trip transmission time; and determining, based on a result of comparing the highest round-trip transmission time to the threshold value and to a multiple of the lowest round-trip transmission time, whether the time period indicates a delay in communication between the I/O subsystem and the control unit requiring at least one of a monitoring action and a recovery action. | 01-19-2012 |
20120117275 | PROVIDING INDIRECT DATA ADDRESSING FOR A CONTROL BLOCK AT A CHANNEL SUBSYSTEM OF AN I/O PROCESSING SYSTEM - An computer program product, apparatus, and method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes the host computer system obtaining a transport command word (TCW) for an I/O operation. The TCW specifies a location of one or more I/O commands and a flag set to indicate that the location is an indirect address. The host computer system extracts the location of the one or more I/O commands and the flag from the TCW, gathers the one or more I/O commands responsive to the location specified by the TCW and the flag, and then forwards the one or more I/O commands to the control unit for execution. | 05-10-2012 |
20120215946 | DISCOVERY AND CONFIGURATION OF DEVICE CONFIGURATIONS - A computer program product is provided for performing a method comprising: receiving, by the host processor, physical configuration information including identification of a location of each physical endpoint connected to the host processor and a plurality of communication paths associated with each physical endpoint; sending at least one message to each physical endpoint on each of the plurality of communication paths in response to receiving the physical configuration information, the at least one message requesting identification of a logical entity at the endpoint, and receiving logical configuration information identifying the logical entity; and generating a data collection accessible by the host processor, the data collection including the physical configuration information and the logical configuration information for each logical entity, and identification of a location of each physical endpoint connected to the host processor and a plurality of communication paths to each logical entity. | 08-23-2012 |
20120221748 | MONITORING NETWORK PERFORMANCE AND DETECTING NETWORK FAULTS USING ROUND TRIP TRANSMISSION TIMES - A method of processing communications includes: receiving transmission data over a selected time interval for each of a plurality of communication paths between a host processor and a control unit configured to control at least one I/O device; calculating an average round-trip transmission time for each of the communication paths over the time interval; comparing an average round-trip transmission time for a communication path having the highest average round-trip transmission time to a threshold value and to a multiple of an average round-trip transmission time for a communication path having the lowest average round-trip transmission time; and determining, based on comparing the highest round-trip transmission time to the threshold value and to a multiple of the lowest round-trip transmission time, whether the time period indicates a delay in communication between the I/O subsystem and the control unit requiring at least one of a monitoring action and a recovery action. | 08-30-2012 |
20120290729 | ESTABLISHING COMMUNICATION PATH GROUP IDENTIFICATION FOR MULTIPLE STORAGE DEVICES - Embodiments of the disclosure relate to setting up a logical path group identification for multiple data storage devices. An aspect of the disclosure concerns a computer implemented method that comprises receiving a host command to establish a group of connection paths between the host and a plurality of storage devices, identifying the group of connection paths, adding each one of the storage devices to the group of connection paths, and reporting to the host those storage devices that could not be successfully added to the group of connection paths. The method maintains host access security to the storage devices by not grouping a device when it is a reset event state. | 11-15-2012 |
20130007300 | FACILITATING TRANSPORT MODE INPUT/OUTPUT OPERATIONS BETWEEN A CHANNEL SUBSYSTEM AND INPUT/OUTPUT DEVICES - A computer program product is configured for performing a method including: generating at least one command message by a channel subsystem of the host computer system, the at least one command message including one or more device command words (DCWs), wherein at least one DCW of the one or more DCWs includes a suppress-length indication (SLI) configured to instruct a control unit to continue to perform the I/O operation in response to the control unit detecting that the data count does not match an amount of data required; receiving an incorrect length (IL) value, the IL value being a first IL value in response to the SLI being a first SLI value and the data count not matching the amount of data required; and responsive to receiving the IL value from the control unit, storing an IL indicator in a subchannel-status word. | 01-03-2013 |
20130007303 | FACILITATING TRANSPORT MODE INPUT/OUTPUT OPERATIONS BETWEEN A CHANNEL SUBSYSTEM AND INPUT/OUTPUT DEVICES - A computer program product is provided for performing an input/output (I/O) processing operation at a host computer system. The computer program product is configured to perform: obtaining a transport command word (TCW) at a channel subsystem for an I/O operation, the TCW including an address of a transport command control block (TCCB) having a transport command area (TCA) configured to hold a first plurality of device command words (DCW) and control data associated with respective DCWs, the first plurality of DCWs including a transfer TCA extension (TTE) DCW that specifies a TCA extension, the TCA extension configured to hold one or more DCWs and control data associated with respective DCWs; gathering the TCCB from one or more locations specified in the TCCB address and transferring the TCCB to the control unit; gathering the TCA extension specified by the TTE DCW; and transferring the TCA extension to the control unit. | 01-03-2013 |
20130007304 | FACILITATING TRANSPORT MODE INPUT/OUTPUT OPERATIONS BETWEEN A CHANNEL SUBSYSTEM AND INPUT/OUTPUT DEVICES - A computer program product is configured for performing a method including: receiving at least one command message specifying an I/O operation at a control unit from a channel subsystem, the at least one command message including one or more device command words (DCWs) having a data count and a suppress-length indication (SLI), the SLI configured to instruct the control unit whether to continue to perform the I/O operation in response to the control unit detecting an incorrect length condition; processing at least one of the one or more DCWs; and returning a transport response message including an incorrect length (IL) value, the IL value being a first IL value in response to the SLI being a first SLI value and the data count not matching the amount of data required, the IL value being a second IL value in response to the SLI being a second SLI value and the data count not matching the amount of data required. | 01-03-2013 |
20130080821 | PROACTIVELY REMOVING CHANNEL PATHS IN ERROR FROM A VARIABLE SCOPE OF I/O DEVICES - A channel path error correction system includes a processor with one or more channels and a switch operatively coupled to the one or more channels of the processor. The system also includes an I/O device including one or more ports, the I/O device being operatively coupled to the switch by the one or more ports; a plurality of control units. Each control unit includes at least one of the channels and at least one of the ports and a memory operable for storing information relating to detected channel path errors associated with each of the plurality of control units. | 03-28-2013 |
20130080822 | PROACTIVELY REMOVING CHANNEL PATHS IN ERROR FROM A VARIABLE SCOPE OF I/O DEVICES - A method includes detecting a channel path error event on an identified channel path; recording channel path error data associated with the detected channel path error event; identifying an scope of the channel path error associated with the identified channel path; determining if the identified channel path is a defective channel path based on the scope of the channel path error; and removing the defective channel path from one or more devices. | 03-28-2013 |
20130179596 | PROVIDING INDIRECT DATA ADDRESSING IN AN INPUT/OUTPUT PROCESSING SYSTEM WHERE THE INDIRECT DATA ADDRESS LIST IS NON-CONTIGUOUS - A method includes configuring a processing circuit to perform: receiving a control word for an I/O operation, forwarding a transport command control block (TCCB) from the channel subsystem to a control unit, gathering data associated with the I/O operation, and transmitting the gathered data to the control unit in the I/O processing system. Gathering the data includes accessing entries of a list of storage addresses that collectively specifying the data. Based on an entry of the list comprising a not-set first flag and a corresponding first storage address, gathering data from a corresponding storage location, and based on an entry of the list comprising a set first flag and a corresponding second storage address, obtaining a next entry of the list from a second storage location. | 07-11-2013 |
20130227178 | Extended Input/Output Measurement Word Facility for Obtaining Measurement Data - An Extended Input/output (I/O) measurement word facility is provided. Provision is made for emulation of the Extended I/O measurement word facility. The facility provides for storing measurement data associated with a single I/O operation in an extended measurement word associated with an I/O response block. In a further aspect, the stored data may have a resolution of approximately one-half microsecond. | 08-29-2013 |
20130246661 | FACILITATING TRANSPORT MODE INPUT/OUTPUT OPERATIONS BETWEEN A CHANNEL SUBSYSTEM AND INPUT/OUTPUT DEVICES - A method of performing an input/output operation includes: generating by a channel subsystem at least one command message including one or more device command words (DCWs), at least one DCW including a data count and a suppress-length indication (SLI) configured to instruct a control unit whether to continue to perform the I/O operation in response to an incorrect length condition; forwarding the at least one command message to the control unit; receiving an incorrect length (IL) value from the control unit and storing an IL indicator in a subchannel-status word, the IL indicator representing the IL value, the IL value being a first IL value in response to a first SLI value and the data count not matching the amount of data required, the IL value being a second IL value in response to a second SLI value and the data count not matching the amount of data required. | 09-19-2013 |
20130282929 | BI-DIRECTIONAL DATA TRANSFER WITHIN A SINGLE I/O OPERATION - A computer program product, apparatus, and a method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The method includes receiving a command block from the channel subsystem, the command block including at least one input command and at least one output command specified by a transport command word (TCW) and associated with the I/O operation, the I/O operation having both input and output data, the TCW specifying a location in the memory of the output data and a location in the memory for storing the input data; receiving the output data specified by the TCW and executing the at least one output command; and forwarding the input data specified by the TCW to the channel subsystem for storage at a location specified by the TCW. | 10-24-2013 |
20130304940 | PROVIDING INDIRECT DATA ADDRESSING FOR A CONTROL BLOCK AT A CHANNEL SUBSYSTEM OF AN I/O PROCESSING SYSTEM - An computer program product, apparatus, and method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The computer program product is provided for performing a method including: obtaining a transport command word (TCW) for an I/O operation, the TCW specifying a location address and indicating whether the TCW directly or indirectly addresses a message for transmitting one or more commands to the control unit; extracting the specified location address from the TCW; obtaining the message from the specified location address based on the TCW indicating direct addressing, the message including one or more I/O commands; gathering one or more I/O commands from command locations specified by a list of addresses identified by the specified location address to form the message based on the TCW indicating indirect addressing; and forwarding the message to the control unit for execution. | 11-14-2013 |
20130339551 | COMMUNICATION PATH SELECTION - A computer system includes a processor configured for detecting initial command response times of a plurality of paths for transmitting signals from the processor to one or more external devices via a plurality of channels, assigning weighted values to the plurality of paths based on the detected initial command response times, and modifying a frequency at which respective paths among the plurality of paths are selected for transmitting the signals based on the weighted values assigned to the respective paths. | 12-19-2013 |
20140281318 | EFFICIENTLY SEARCHING AND MODIFYING A VARIABLE LENGTH QUEUE - Embodiments relate to ensuring that serialization is maintained between separate transactions while searching and/or modifying a variable length queue is provided. An aspect includes searching a queue using a transaction. A first sequence number is retrieved from a queue header and a second sequence number is retrieved from local storage for the transaction. The first sequence number is compared with the second sequence number according to embodiments. The search of the queue is resumed using an address of a next element saved from a previous transaction responsive to the first sequence number matching the second sequence number. The search of the queue is restarted at a first element responsive to the first sequence number not matching the second sequence number. | 09-18-2014 |
20140297891 | PROVIDING INDIRECT DATA ADDRESSING FOR A CONTROL BLOCK AT A CHANNEL SUBSYSTEM OF AN I/O PROCESSING SYSTEM - An computer program product, apparatus, and method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The computer program product is provided for performing a method including: sending a transport command word (TCW) to an I/O subsystem, the TCW specifying a location address and indicating whether the TCW directly or indirectly addresses a message; extracting the location address from the TCW; obtaining the message from the specified location address based on the TCW indicating direct addressing, the message including the one or more I/O commands; gathering the one or more I/O commands from command locations specified by a list of addresses identified by the specified location address to form the message based on the TCW indicating indirect addressing; and generating a message including the one or more I/O commands. | 10-02-2014 |
20140379948 | PROVIDING INDIRECT DATA ADDRESSING IN AN INPUT/OUTPUT PROCESSING SYSTEM WHERE THE INDIRECT DATA ADDRESS LIST IS NON-CONTIGUOUS - A computer program product for processing input/output (I/O) data is provided for performing a method, which includes receiving a control word having an indirect data address including a starting location of a list of storage addresses, gathering the data and transmitting gathered data to a control unit in the I/O processing system. Gathering includes accessing an entry of the list, the entry located at an entry storage location and including an address. Based on the entry of the list indicating that the address is a data address, data is gathered from a data storage location, and a next entry of the list is accessed. Based on the entry of the list indicating that the address is an address of a next entry of the list, the next entry of the list is obtained from another storage location that is located non-contiguously to the entry storage location. | 12-25-2014 |
20150019580 | EFFICIENTLY SEARCHING AND MODIFYING A VARIABLE LENGTH QUEUE - A method of ensuring that serialization is maintained between separate transactions while searching and/or modifying a variable length queue includes searching a queue using a transaction. A first sequence number is retrieved from a queue header and a second sequence number is retrieved from local storage for the transaction. The first sequence number is compared with the second sequence number according to embodiments. The search of the queue is resumed using an address of a next element saved from a previous transaction responsive to the first sequence number matching the second sequence number. The search of the queue is restarted at a first element responsive to the first sequence number not matching the second sequence number. | 01-15-2015 |
20150074295 | BI-DIRECTIONAL DATA TRANSFER WITHIN A SINGLE I/O OPERATION - A computer program product, apparatus, and a method for facilitating input/output (I/O) processing for an I/O operation at a host computer system configured for communication with a control unit. The method includes receiving, by a control unit, a command block configured to hold a plurality of commands including an input command and/or an output command, the plurality of commands specified by a transport command word (TCW) including a read indicator configured to indicate whether the I/O operation includes input data and a write indictor configured to indicate whether the I/O operation includes output data; based on the command block holding at least one output command, receiving the output data and executing the at least one output command; and based on the command block holding at least one input command, forwarding the input data to the channel subsystem for storage at a location specified by the TCW. | 03-12-2015 |