Abstract: A storage system has a plurality of control modules for controlling a plurality of storage devices, which make mounting easier with maintaining low latency response even if the number of control modules increases. A plurality of storage devices are connected to the second interface of each control module using back end routers, so that redundancy for all the control modules to access all the storage devices is maintained. Also the control modules and the first switch units are connected by a serial bus, which has a small number of signals, constituting the interface by using the back panel. By this, mounting on the printed circuit board becomes possible.

Abstract: In response to a request from a central processing unit (CPU) 11 (i.e., firmware) of a node 10, a transfer control unit 14a of a direct memory access (DMA) controller 14 transmits a message and data to another discretionary node 3 by way of a serial bus 1, a switch 2 or the like. In this event, the firmware stores data to be transmitted, a message, and a descriptor thereof in memory 12. In the case of requesting the transmission of the message, the descriptor contains a flag indicating “whether or not there is a need to wait for a response from the data transmission destination”. If the flag is set to ON, the transfer control unit 14a notifies the firmware of a simulated completion immediately instead of waiting for a completion response from the transmission destination node 3.

Abstract: To be able to transmit a response packet to the original request node after a bus ID/a device ID is replaced in the PCI-Express switch for a PCI-Express communication system, a unique node ID for indicating each node is set to the nodes. Additionally, it is confirmed whether or not the packet is transferred in the correct order in a series of packet transfers. For that purpose, a sequence code indicating the sequence number of a packet in a series of packet transfer is set in an address field of a packet of data transfer.

Abstract: A file control system performing DMA (direct memory access) transfer is provided. The file control system includes file control devices, and each of the file control devices is provided between a host computer and an external storage device. A first file control device among the file control devices checks for errors in the data read from a memory, changes the error detection code added to the read data from a first error detection code to a second error detection code, changes at least a part of the data when an error is detected, and executes DMA-transfer of the data, which is changed or is not changed, to a second file control device of the transfer destination.

Abstract: A computer system enable system operation by hiding the peculiarity of an upstream port of a switch in a computer system in which a plurality of CPU units are interconnected by a PCI Express switch. When a CPU unit, which is connected to the upstream port of a serial connect switch interconnecting the plurality of CPU units, is unable to operate, and the links between the CPU units and the switch cannot be established, a management controller in the switch unit is selected as a device of the upstream port.

Abstract: Before the link of each port of a switch provide with a plurality of ports for interconnecting a plurality of process nodes by a serial bus is established, it is checked whether each process node is mounted. Then, of the plurality of ports, a port to which one of mounted process nodes is connected is assigned as an upstream port and the other ports are assigned as downstream ports.

Abstract: A storage system has a plurality of control modules for controlling a storage device for accesses from a mainframe host and an open system host respectively supporting different protocols. An open channel adaptor and a mainframe channel adaptor are separately provided. The mainframe channel adaptor is connected to a plurality of control managers via front routers and performs parallel write access from the mainframe host for mirroring. In the write processing for the mainframe host, the connection is maintained until the completion of processing. In particular, even in case of a write miss, disk read processing can be performed in parallel, thus contributing to the high-speed processing in case of the write miss. Further, for an access from the open system host, a high throughput can be obtained.

Abstract: A system and method for fault containment and error handling within a domain in a partitioned computer system includes a system manager having read and write access to a resource definition table. The system manager is adapted to quiesce the system when failure occurs within a domain, identify an allocated resource associated with the failed domain, identify a non-failed domain, and exit the quiesce mode for the non-failed domain, thereby containing a failure within the failed domain. The system manager further handles an error within the failed domain by deallocating a resource allocated to the failed domain so that the resource becomes available to non-failed domains.

Abstract: In response to a request from a central processing unit (CPU) 11 (i.e., firmware) of a node 10, a transfer control unit 14a of a direct memory access (DMA) controller 14 transmits a message and data to another discretionary node 3 by way of a serial bus 1, a switch 2 or the like. In this event, the firmware stores data to be transmitted, a message, and a descriptor thereof in memory 12. In the case of requesting the transmission of the message, the descriptor contains a flag indicating “whether or not there is a need to wait for a response from the data transmission destination”. If the flag is set to ON, the transfer control unit 14a notifies the firmware of a simulated completion immediately instead of waiting for a completion response from the transmission destination node 3.

Abstract: A system and method for fault containment and error handling within a domain in a partitioned computer system includes a system manager having read and write access to a resource definition table. The system manager is adapted to quiesce the system when failure occurs within a domain, identify an allocated resource associated with the failed domain, identify a non-failed domain, and exit the quiesce mode for the non-failed domain, thereby containing a failure within the failed domain. The system manager further handles an error within the failed domain by deallocating a resource allocated to the failed domain so that the resource becomes available to non-failed domains.

Abstract: A storage system has a plurality of control modules for controlling a storage device for accesses from a mainframe host and an open system host respectively supporting different protocols. An open channel adaptor and a mainframe channel adaptor are separately provided. The mainframe channel adaptor is connected to a plurality of control managers via front routers and performs parallel write access from the mainframe host for mirroring. In the write processing for the mainframe host, the connection is maintained until the completion of processing. In particular, even in case of a write miss, disk read processing can be performed in parallel, thus contributing to the high-speed processing in case of the write miss. Further, for an access from the open system host, a high throughput can be obtained.

Abstract: A method and system enables dynamic support of memory mapping devices in a multi-node computer system. One of central process unit (CPU) nodes determines a total amount of MMIO address spaces that are needed for all MMIO devices and generates an optimized granularity to support the total amount of MMIO address spaces. Based on the granularity, a CPU node controller configures MMIO range registers of the interconnect and other MMIO registers in IO nodes and CPU node controllers to support dynamic changes of MMIO address space requirements of the system.

Abstract: To be able to transmit a response packet to the original request node after a bus ID/a device ID is replaced in the PCI-Express switch for a PCI-Express communication system, a unique node ID for indicating each node is set to the nodes. Additionally, it is confirmed whether or not the packet is transferred in the correct order in a series of packet transfers. For that purpose, a sequence code indicating the sequence number of a packet in a series of packet transfer is set in an address field of a packet of data transfer.

Abstract: A system and method for passing messages between domains with low overhead in a multi-node computer system. A CPU node in a sending domain issues a request to a memory node in a receiving domain using memory-mapped input/output window. This causes the message to be transmitted to a coherent space of the receiving domain. All messages are cache-line in size. A small portion of each cache line, cyclic counter field, is overwritten before the cache line is written in the coherent address space of the receiving domain. A massaging driver polls the cyclic count field of the cache line in the processor cache to determine when the next message is written in the coherent address space of the receiving domain. This allows the CPU to detect when the last received message is written into the coherent address space of the receiving domain without generating transactions on CPU interface.

Abstract: A mechanism for balancing message traffic in a multi-chassis fully interconnected computer system partitioned into multiple domains allows the system to identify I/O transactions, to route I/O transactions over inter-domain cables, and to route non-I/O transactions over intra-domain cables. This beneficially reduces message traffic congestion on intra-domain cables.

Abstract: A storage system have a control module which controls a plurality of disk storage devices, and which realizes reading/writing of system information even when problems arise in the path with a plurality of disk devices. A system disk device unit which stores system information is incorporated within the control modules which control a plurality of disk storage devices. The control modules can read/write system information even without accessing the disk storage devices.

Abstract: A computer system enable system operation by hiding the peculiarity of an upstream port of a switch in a computer system in which a plurality of CPU units are interconnected by a PCI Express switch. When a CPU unit, which is connected to the upstream port of a serial connect switch interconnecting the plurality of CPU units, is unable to operate, and the links between the CPU units and the switch cannot be established, a management controller in the switch unit is selected as a device of the upstream port.

Abstract: A file control system of the present invention is a file control system performing DMA transfer and comprising a plurality of file control devices, each of which is provided between a host computer and an external storage device, a first file control device among the plurality of file control devices, checks the consistency between the data read from a memory and the first error detection code given in advance to the data, changes the error detection code added to the read data from the first error detection code to a second error detection code, when the inconsistency is detected by the check, changes at least a part of the data comprising the second error detection code and the data associated with the second error detection code, and executes DMA-transfer of the data which is changed or is not changed to a second file control device of the transfer destination.

Abstract: Before the link of each port of a switch provide with a plurality of ports for interconnecting a plurality of process nodes by a serial bus is established, it is checked whether each process node is mounted. Then, of the plurality of ports, a port to which one of mounted process nodes is connected is assigned as an upstream port and the other ports are assigned as downstream ports.

Abstract: A method and system transfers data between intra-node firmware and inter-nodes firmware in a multi-node computer system using reduced hardware resources. A set of control codes and data transfer functions are provided to enable data communications between computer nodes and inter-nodes controller through a one-byte control module and a one-byte data module.