Abstract: One or more embodiments include scheduling a new operation to be periodically executed. A start time for a new operation, to be periodically executed, is determined based on the start times of previously scheduled operations. The difference in value between a candidate start time and a start time of a previously scheduled operation is used to compute a cost for the candidate start time. A candidate start time, of all the candidate start times, with a lowest cost may be selected as the start time for the new operation.

Abstract: One or more embodiments include scheduling a new operation to be periodically executed. A start time for a new operation, to be periodically executed, is determined based on the start times of previously scheduled operations. The difference in value between a candidate start time and a start time of a previously scheduled operation is used to compute a cost for the candidate start time. A candidate start time, of all the candidate start times, with a lowest cost may be selected as the start time for the new operation.

Abstract: A data storage system includes a plurality of servers, a plurality of external interface providers each deployed on one of the servers, and a plurality of data storage controllers each deployed on one of the servers. Each of the providers is configured to receive a data access request, to identify one of the controllers that can satisfy the request, and to forward the request to the identified controller. The system further includes a plurality of data storage modules independent of the servers. The providers, controllers and modules are in communication with each other. Each of the controllers exclusively manages a portion of data content in at least one of the modules, and satisfies data access requests received from the providers by accessing the portion of data content in the at least one module.

Abstract: A data storage system manager includes one or more servers, at least one data collector deployed on at least one of the servers, at least one policy engine deployed on at least one of the servers, and at least one configuration manager deployed on at least one the servers. The at least one data collector is configured to collect resource utilization information including data storage wear rate of data storage system data storage modules. The at least one policy engine is configured to evaluate the collected information and to initiate changes to a configuration of the data storage system based on data storage wear rate and work load distribution policies. The at least one configuration manager is configured to implement the changes initiated by the at least one policy engine to control the data storage wear rate and a skew of the work load distribution within the data storage system.

Abstract: A data storage system includes an input/output server and a storage unit. The input/output server includes a processor, memory, and a host channel adapter. The storage unit includes a processor, memory, and a storage module. The storage module includes a storage controller, and an interface block for connecting the storage module to a corresponding memory-mapped interface. The storage unit further includes a host channel adaptor. The storage unit host channel adapter is connected to a corresponding memory-mapped interface. The storage unit host channel adapter is capable of remote direct memory access to the input/output server. Protocol translation logic is configured to intercept a memory access request from the storage controller, and initiate a corresponding remote direct memory access to the input/output server through the storage unit host channel adapter and the input/output server host channel adapter.

Abstract: A data storage system includes an input/output server and a storage unit. The input/output server includes a processor, memory, and a host channel adapter. The storage unit includes a processor, memory, and a storage module. The storage module includes a storage controller, and an interface block for connecting the storage module to a corresponding memory-mapped interface. The storage unit further includes a host channel adaptor. The storage unit host channel adapter is connected to a corresponding memory-mapped interface. The storage unit host channel adapter is capable of remote direct memory access to the input/output server. Protocol translation logic is configured to intercept a memory access request from the storage controller, and initiate a corresponding remote direct memory access to the input/output server through the storage unit host channel adapter and the input/output server host channel adapter.

Abstract: A data storage system includes a plurality of servers, a plurality of external interface providers each deployed on one of the servers, and a plurality of data storage controllers each deployed on one of the servers. Each of the providers is configured to receive a data access request, to identify one of the controllers that can satisfy the request, and to forward the request to the identified controller. The system further includes a plurality of data storage modules independent of the servers. The providers, controllers and modules are in communication with each other. Each of the controllers exclusively manages a portion of data content in at least one of the modules, and satisfies data access requests received from the providers by accessing the portion of data content in the at least one module.

Abstract: A data storage system manager includes one or more servers, at least one data collector deployed on at least one of the servers, at least one policy engine deployed on at least one of the servers, and at least one configuration manager deployed on at least one the servers. The at least one data collector is configured to collect resource utilization information including data storage wear rate of data storage system data storage modules. The at least one policy engine is configured to evaluate the collected information and to initiate changes to a configuration of the data storage system based on data storage wear rate and work load distribution policies. The at least one configuration manager is configured to implement the changes initiated by the at least one policy engine to control the data storage wear rate and a skew of the work load distribution within the data storage system.

Abstract: In a disk-based data storage system, a controller configured to control a reference count regeneration operation, the controller includes a control register, an address register, a status register, a boundary register, and an embedded memory. The control register may be configured to set up and initiate program instructions that are executed by at least one processor. The address register may be configured as a cache address pointer and correspond to at least one of a sort output list pointer, a virtual track table input list pointer, a reference list pointer, a track number table pointer, and a reference count mis-compare list pointer. The status register may be configured to indicate status of a routine. The routine includes at least one of a radix sort, a reference list count, a combine counts, and a merger of the reference list count into the TNT to generate an updated TNT.

Abstract: In a data storage system in which there can be multiple references to a single instance of an object, a method for regenerating the number of references to each object instance. The method includes radix sorting the references to the objects to generate a reference list, counting the references to each unique object and merging the counts with the object descriptions, placing the count of the number of references to each object into the respective object description. The sorting, counting and merging techniques used by this method generate sequential memory access patterns that enable efficient use of low-cost memory and block-oriented memory access interconnect fabric protocols. Furthermore, multiple instances of the sorting, counting and merging processes can be used in parallel to reduce the time required to regenerate the reference counts for a large number of objects.

Abstract: A method for configuring a computer network that includes a full duplex bi-directional first port and an initiator that can issue a request for the first port to assume a state. The first port, when in a first state, is able to bi-directionally communicate with a full duplex bi-directional second port, and when in a second state, is coupled to itself by having an output thereof coupled to an input thereof. The method comprises inhibiting the initiator from issuing the request, sending data to the initiator describing a desired state of the first port, and enabling the initiator to issue the request for the first port to assume the desired state.

Abstract: A method for detecting and remembering multiple sequential access patterns made from a host to a memory system having one or more logical storage devices. Once a sequential access pattern is detected, one or more tracks are requested to be prestaged ahead of the current access request. The number of tracks requested to be prestaged ahead may be responsive to the amount of storage available in the cache memory. One list is provided for each logical storage device. Each list has multiple entries and is logically divided into two parts. A sequential part contains entries for access streams which the system has determined are sequential and for which the system may have prestaged one or more tracks into cache. A candidate part contains information about recent host accesses which have not as yet been determined to be sequential. The entries within each of the two parts of the list are logically ordered in a most-recently-used fashion.

Abstract: A system and method for providing a trusted machine state in a data processing system is disclosed. The data processing system includes a memory. The trusted machine state is stored in a first portion of the memory. The method and system include saving the trusted machine state in a second portion of the memory and reinitializing a portion of the memory. The portion of memory is separate from the second of memory. The method and system further include restoring the trusted machine state in the memory. According to the method and system disclosed herein, the data processing system may recover from failures and resume operation. Moreover, a non-disruptive code load, in which a new program can be loaded without disrupting system operations, may be performed.

Abstract: The present data file storage management system for snapshot copy operations maintains a two level mapping table which enables the data files to be copied using the snapshot copy process and only having to update a single corresponding mapping table entry when the physical location of the data file is changed. The snapshot copy updates to the contents of the first level of the two level mapping table are stored on the backend data storage devices to provide a record of the snapshot copy operation which can be used to recover the correct contents of the mapping table. This record of the snapshot copy operations remains valid even though the physical location of a copied data file instance is subsequently changed. Furthermore, the physical storage space holding the updated portions of the first level of the two level mapping table can be managed using techniques like those used to manage the physical storage space holding data file instances.