Abstract: Various embodiments for preserving data redundancy in a data deduplication system in a computing environment are provided. An indicator is configured. The indicator is provided with a selected data segment to be written through the data deduplication system to designate that the selected data segment must not be subject to a deduplication operation, such that repetitive data can be written stored on physical locations despite being identical.

Abstract: A method for increasing the efficiency of a “copy-on-write” operation performed on an SSD to extend the life of the SSD is disclosed herein. In one embodiment, such a method includes receiving a first logical address specifying a logical location where new data should be written to an SSD. The first logical address maps to a first physical location, storing original data, on the SSD. The method further receives a second logical address specifying a logical location where the original data should be available on the SSD. The second logical address maps to a second physical location on the SSD. To efficiently perform the copy-on-write operation, the method writes the new data to a new physical location on the SSD, maps the first logical address to the new physical location, and maps the second logical address to the first physical location. A corresponding apparatus is also disclosed.

Abstract: A periodic rotational vibration check for storage devices to compensate for varying loads is disclosed. A variable representing rotational vibration status is maintained in a rotational vibration log. The variable is processed to determine whether a storage device exhibits a rotational vibration issue. Workload analysis is performed to identify a change to the workloads run on physically separate hardware to resolve the rotational vibration issue and thus eliminate the need for more expensive hardware.

Abstract: A periodic rotational vibration check for storage devices to compensate for varying loads is disclosed. A variable representing rotational vibration status is maintained in a rotational vibration log. The variable is processed to determine whether a storage device exhibits a rotational vibration issue. Workload analysis is performed to identify a change to the workloads run on physically separate hardware to resolve the rotational vibration issue and thus eliminate the need for more expensive hardware.

Abstract: Provided are a method, system, and program for adding a fourth device to a network including a first, second, and third devices, wherein the first and second devices are directly connected to the third device. The fourth device is directly connected to the third device while the first and second devices remain connected to the third device, and wherein the first and second devices continue to have access to the third device while the fourth device is connected to the third device.

Abstract: Provided are a method, system, and article of manufacture for determining modified data in cache for use during a recovery operation. An event is detected during which processing of writes to a storage device is suspended. A cache including modified data not destaged to the storage device is scanned to determine the data units having modified data in response to detecting the event. The data units having the modified data is indicated in a backup storage. The indication of the data units having the modified data in the backup storage is used during a recovery operation.

Abstract: An apparatus, system, and method are disclosed for providing a redundant array of inexpensive disks (“RAID”) storage subsystem within a processor blade enclosure. A first RAID controller blade is included and configured to fit in a processor blade enclosure. At least one processor in communication with the first RAID controller blade is included. A disk enclosure blade is provided that includes a plurality of hard disk drives. The disk enclosure blade is configured to fit in the processor blade enclosure and the hard disk drives are in communication with the first RAID controller blade.

Abstract: A computer system uses a Fiber Channel Arbitrated Loop (FC-AL) network to communicate with mass storage devices. The FC-AL network provides alternative communication paths to the mass storage devices. The FC-AL communication network includes a first (60) FC-AL controller within the FC-AL switch (50). A first FC-AL mass storage drive (56) has second (80) and third (82) FC-AL controllers. A first output of the first FC-AL controller is coupled to a first input of the second FC-AL controller, and a second output of the first FC-AL controller is coupled to a first input of the third FC-AL controller. A second FC-AL mass storage drive (94) has fourth (96) and fifth (98) FC-AL controllers. A first output of the second FC-AL controller is coupled to a first input of the fourth FC-AL controller, and a first output of the third FC-AL controller is coupled to a first input of the fifth FC-AL controller. The alternative communication paths to the mass storage devices reduces incident of disk drive access failure.

Abstract: An apparatus, system, and method are disclosed for providing a redundant array of inexpensive disks (“RAID”) storage subsystem within a processor blade enclosure. A first RAID controller blade is included and configured to fit in a processor blade enclosure. At least one processor in communication with the first RAID controller blade is included. A disk enclosure blade is provided that includes a plurality of hard disk drives. The disk enclosure blade is configured to fit in the processor blade enclosure and the hard disk drives are in communication with the first RAID controller blade.

Abstract: A periodic rotational vibration check for storage devices to compensate for varying loads is disclosed. A variable representing rotational vibration status is maintained in a rotational vibration log. The variable is processed to determine whether a storage device exhibits a rotational vibration issue. Workload analysis is performed to identify a change to the workloads run on physically separate hardware to resolve the rotational vibration issue and thus eliminate the need for more expensive hardware.

Abstract: An apparatus, system, and method are disclosed for limiting failures in redundant signals. A coordination module generates a power status signal for each of a plurality of power modules. An input module receives a source signal. A signal generation module generates a plurality of output signals from the source signal and at least one power status signal. The output signals are not asserted if at least one power supply is operational. If a device of the signal generation module malfunctions, no more than one output signal is erroneously asserted.

Abstract: An apparatus, system, and method are disclosed for maximizing power system holdup time during loss of input power. An energy storage module is included to deliver energy from an output stage of a first power supply to a bus. A power loss module is included to detect loss of power transmitting capability from an input stage of the first power supply to the output stage of the first power supply. A set-point reduction module is included to reduce an output voltage of the first power supply in response to the power loss module detecting loss of power transmitting capability. An isolation module is included to prevent energy flow from the energy storage module to the bus when the output voltage of the first power supply is lower than a voltage on the bus sustained by a second power supply.

Abstract: An apparatus, system, and method are disclosed for securely providing power supply commands. A security feature is added to the remote management of power-on and power-off sequences. The feature allows for multiple controller nodes to receive a command to initiate a power sequence. Each controller node possesses a unique identifier. The nodes compare the received command with received commands of other nodes to confirm that each node received identical power commands. The security feature prevents inadvertent power commands from being received and executed by a single controller node. The unique identifier of each node must be provided before execution of the power command occurs.

Abstract: The method forms a plurality of DMA data payloads each comprising a plurality of first sectors, and sends to a sector format conversion device one or more of those DMA data payloads. The method then overlays the (i)th DMA data payload onto part or all of a plurality of second sectors to form the (i)th converted DMA data payload, enqueues that (i)th converted DMA data payload in a data queue, transmits that (i)th converted DMA data payload to a data storage device, and writes the (i)th converted DMA data payload to an information storage medium.

Abstract: An apparatus for limiting volatile computer memory based on available energy in an auxiliary power source comprises an energy monitor module configured to determine an amount of available energy in the auxiliary power source. Also provided is a memory status module configured to determine an amount of volatile computer memory allocated for use in a computer and a memory adjustment module configured to adjust the amount of volatile computer memory allocated for use in the computer based on the amount of available energy in the auxiliary power source.

Abstract: Provided are a method, system, and program for adding a fourth device to a network including a first, second, and third devices, wherein the first and second devices are directly connected to the third device. The fourth device is directly connected to the third device while the first and second devices remain connected to the third device, and wherein the first and second devices continue to have access to the third device while the fourth device is connected to the third device.

Abstract: A method, apparatus and program storage device for providing data integrity using check data and other metadata on a formatted storage medium.

Abstract: A data storage subsystem which reduces seek time, by defining a logical storage space wherein part of the logical storage space is defined to correspond to a primary storage space of a first physical data storage device, and correspond to a secondary storage space of a second physical data storage device, and another part of the logical storage space is defined to correspond to a primary storage space of the second physical data storage device, and correspond to a secondary storage space of the first physical data storage device. For hard disk drives having an arm assembly with a read/write head, the average seek distance for both drives reduced, since the pivoting arm assembly need not travel as far to reach each physical storage address within a primary storage area. The invention may additionally take advantage of geometric or other aspects of the storage devices which result in some portion of the device having a faster access time that another portion.

Abstract: Disclosed is a bridge system and method for prefetching data to return to a read request from an agent. The bridge system includes at least one memory device including a counter indicating a number of prefetch operations to perform to prefetch all the requested data, a first buffer capable of storing prefetch requests, and a second buffer capable of storing read data. Control logic implemented in the bridge system includes means for queuing at least one prefetch operation in the first buffer while the counter is greater than zero. The control logic then executes a queued prefetch operation, subsequently receives the prefetched data, and stores the prefetched data in the second buffer. The stored prefetched data is returned to the requesting agent.

Abstract: Disclosed is a system for processing read/write transactions from a plurality of agents over a bus. The bridge includes at least one request buffer for each agent in communication with the bridge. The request buffer for an agent buffers transactions originating from that agent. The bridge further includes a return buffer for each agent in communication with the bridge. The return buffer for an agent buffers return data in connection with a transaction. Address translation circuitry is in communication with the bus and request and return buffers. The address translation circuitry locates a request buffer to queue the transaction, such that a transaction is stored in the request buffer corresponding to the agent that originated the transaction. Further, the address translation circuitry stores read return data for a read transaction in the return buffer corresponding to the agent originating the transaction.