摘要:
A method for combining partial records into a single direct memory access (DMA) operation for a count key data (CKD) protocol in a computer environment is provided. In an initiator processor of the computer environment, a number of the partial records to be prefetched is determined by gathering a plurality of descriptor information for a command according to a predetermined algorithm having a plurality of assumptions for the command. The number of partial records is prefetched. At least one of record headers and record keys of the number of partial records are concatenated into the single DMA operation. The DMA operation is forwarded to a receiver process to be completed.
摘要:
Method, system and computer program product embodiments for, in an input/output (I/O) link handling complex instruction chains, a messaging scheme incorporating a method of error recovery between an initiator processor and a receiver processor, are provided. An operation initiation message is been sent from the initiator processor to the receiver processor for the receiver processor to begin work on an operation. If determined to be necessary, a terminate operation message is sent from the initiator processor to the receiver processor. The initiator processor withholds sending additional messages for the operation until a terminate operation response message is received. Once the terminate operation message is received, outstanding messages in process are flushed from the receiver processor. The receiver processor withholds sending additional messages to the initiator processor as the outstanding messages are completed. The terminate operation response message is sent from the receiver processor to the initiator processor.
摘要:
A method of packaging locate record commands for device command word (DCW) processing is provided. A first locate record command is packaged into DCW prefix parameter data. The first locate record command includes first search and first seek arguments, a first intent count argument, a first transfer length factor argument, and a plurality of remaining arguments. A plurality of truncated locate record commands is embedded in the DCW prefix parameter data as concatenations to the first locate record command. Each of the plurality of truncated locate record commands include a unique search argument, intent count argument, and transfer length factor argument. Seek argument parameters for each of the plurality of truncated locate record commands are calculated by taking an offset from the first seek argument and the first search argument, applying the offset to each of the plurality of truncated locate record commands. The plurality of remaining arguments is shared.
摘要:
A method for facilitating input/output (I/O) communication for a processing operation is provided. An interrogate command is obtained by an I/O communications adapter. The interrogate command queries for status information of the processing operation to be provided in an interrogate response. A fixed number of resources and a time allocated to the interrogate command is throttled by pre-allocating the fixed number of resources needed for the interrogate command, and maintaining a timestamp for a interrogate message. The interrogate message is forwarded from the I/O communications adapter to a control unit. If the interrogate response is not received by the I/O communications adapter within a limited timeout period as measured by the timestamp, or if the interrogate message is received while the fixed number of pre-allocated resources are in use, the I/O communications adapter returns a busy response indicating the control unit is busy to prevent overrunning the control unit.
摘要:
Provided are a method, system, and article of manufacture, wherein a primary storage control unit receives an information unit from a remote host over a fiber channel connection, wherein persistent information unit pacing is implemented over the fiber channel connection. Information is maintained on how many large writes have been received at the primary storage control unit over at least one logical path established over the fiber channel connection between the primary storage control unit and the remote host, wherein a large write is an input/output (I/O) operation for which a number of data information units that are processed exceeds a default value of an information unit pacing credit. The primary storage control unit adjusts an information unit pacing parameter included in a response sent from the primary storage control unit to the remote host, wherein the adjusting is based at least on the information maintained on how many large writes have been received at the primary storage control unit over the at least one logical path.
摘要翻译:提供了一种方法,系统和制品,其中主存储控制单元通过光纤通道连接从远程主机接收信息单元,其中持续信息单元起搏在光纤通道连接上实现。 维持在通过在主存储控制单元和远程主机之间的光纤通道连接上建立的至少一个逻辑路径在主存储控制单元处接收到多少大写入的信息,其中大写是输入/输出( I / O)操作,其中处理的多个数据信息单元超过信息单元起搏信用的默认值。 主存储控制单元将从主存储控制单元发送的响应中包括的信息单元起搏参数调整到远程主机,其中调整至少基于在主存储器上已经接收到多少大写入的信息 所述至少一个逻辑路径上的控制单元。
摘要:
Provided are a method, system, and article of manufacture, wherein a primary storage control unit receives an information unit from a remote host over a fibre channel connection. The primary storage control unit adjusts an information unit pacing parameter included in a response sent from the primary storage control unit to the remote host, wherein the information unit pacing parameter indicates the number of information units that the remote host is allowed to send to the primary storage control unit without waiting for any additional response from the primary storage control unit.
摘要:
A method is provided to protect against ill-behaved microcode by balancing between an actual occurrence of a hardware problem and a microcode bug setting a flag appearing as a hardware problem. In this method, the error recovery is performed only on a single piece of hardware and no further error recovery action is taken on other pieces of similar hardware. The approach addresses the problem by treating a hit on one card as a hardware problem, but as a bug on subsequent cards. The invention keeps track of whether or not the same event has occurred on the same type of hardware so not to take action on more than one instance of the hardware. Subsequent hits on another instance of the hardware will not trigger the hardware related recovery on additional hardware.
摘要:
A method of packaging a plurality of repeating commands for device command word (DCW) processing in a computer environment having an I/O link handling complex instruction chains for a processing operation is provided. Locate record information is packaged into DCW prefix parameter data. The locate record information includes an intent count argument. The plurality of repeating commands are embedded as a truncated concatenation to the first locate record information. The plurality of repeating commands are identified by redefining the intent count argument for the plurality of repeating commands as a repeat count argument using a flag argument incorporated into the locate record information. The repeat count argument indicates a number of times for a control unit in the computer environment to execute the plurality of repeating commands.
摘要:
Provided are a method, system, and article of manufacture, in which a logical path is established between a control unit and a channel over a fiber channel connection. Code for persistent information unit pacing is loaded into the control unit and the channel. An indicator is set in node descriptors of the control unit and the channel to indicate concurrent enablement of persistent pacing while retaining the established logical path between the control unit and the channel.
摘要:
Disclosed are a method, apparatus, and computer program product to reduce the detrimental effects of taking resources offline. A resource is taken offline in a storage network by quiescing activity to the resource providing notification that the resource will become unavailable, and taking the resource offline.