Abstract: A method for caching a block of data. The method including receiving a request to store the block and determining whether an active cache is able to expand. If the active cache is able to expand, then expanding the active cache to obtain an expanded active cache, and storing the block in the expanded active cache. If the active cache is not able to expand, then determining whether evictable blocks are present in the victim cache. If evictable blocks are present in the victim cache, then evicting a sufficient number of the evictable blocks from the victim cache to facilitate storing the block in the active cache, where the evictable blocks in the victim cache are compressed.

Abstract: A method, processing node, and computer readable medium for propagating data using mirrored lock caches are disclosed. The method includes coupling a first mirrored lock cache associated with a first processing node to a bus that is communicatively coupled to at least a second mirrored lock cache associated with a second processing node in a multi-processing system. The method further includes receiving, by the first mirrored lock cache, data from a processing node. The data is then mirrored automatically so that the same data is available locally at the second mirrored lock cache for use by the second processing node.

Abstract: Garbage collection in heterogeneous multiprocessor systems is provided. In some illustrative embodiments, garbage collection operations are distributed across a plurality of the processors in the heterogeneous multiprocessor system. Portions of a global mark queue are assigned to processors of the heterogeneous multiprocessor system along with corresponding chunks of a shared memory. The processors perform garbage collection on their assigned portions of the global mark queue and corresponding chunk of shared memory marking memory object references as reachable or adding memory object references to a non-local mark stack. The marked memory objects are merged with a global mark stack and memory object references in the non-local mark stack are merged with a “to be traced” portion of the global mark queue for re-checking using a garbage collection operation.

Abstract: A system, method, and a computer readable for protecting content of a memory page are disclosed. The method includes determining a start of a semi-synchronous memory copy operation. A range of addresses is determined where the semi-synchronous memory copy operation is being performed. An issued instruction that removes a page table entry is detected. The method further includes determining whether the issued instruction is destined to remove a page table entry associated with at least one address in the range of addresses. In response to the issued instruction being destined to remove the page table entry, the execution of the issued instruction is stalled until the semi-synchronous memory copy operation is completed.

Abstract: Methods copying data from one location to another in a main memory of a cell processor are disclosed. A portion of the data is transferred a first main memory location to the local store of one or more SPU and then transferred from the local store to a second main memory location.

Abstract: Access bit contained in a page table entry is utilized for reducing the number of translation buffer flushes that an operating system needs to issue. A translation buffer flush occurs only when a page table entry is to become invalid and the Access bit of the page table entry is set.

Abstract: A method for managing multiple logical volumes in a data storage system, including providing physical storage of a given capacity within the data storage system, and adding a logical volume of a given size within the data storage system so as to cause a total amount of logical storage of the logical volumes in the data storage system to be greater than the given capacity of the physical storage. The method includes verifying, in response to a write command to store data in the logical volume, that a physical storage location is available in the physical storage and, if the physical storage location is available, then storing the data at the physical storage location.

Abstract: In a system having an internal storage system and an external storage system, a technique is provided for allowing the external storage system to inherit performance parameters from the internal storage system. Management tables are established in each of the two storage systems, and data pertaining to desired operational characteristics stored in the management table in the internal storage system. That information is transferred to the external storage system and used control its operations in accordance with the desired performance parameter.

Abstract: An information system includes a primary storage system (PSS), a host, an external storage system (ESS), and a management host. The PSS uses virtual devices to treat logical devices in the ESS as if they were logical devices in the PSS. The ESS logical devices are configured using multiple disks for providing redundancy, such as in a RAID configuration, to enable migration of data following hardware failure in the ESS. When a disk forming part of an ESS logical device fails, the management host detects the failure and judges whether the ESS logical device is used by the PSS to form a virtual device. If the ESS logical device is used to form a virtual device, then the management host issues a migration request. In response to the migration request, the PSS migrates data from the ESS logical device to a logical device in the PSS to avoid data loss.

Abstract: A method for caching a block, which includes receiving a request to store the block in a cache and determining whether the cache is able to expand. If the cache is not able to expand, then determining whether evictable blocks are present in the cache and, if evictable blocks are present in the cache determining whether a total size of the evictable blocks is greater than or equal to a size of the block, evicting a sufficient number of the evictable blocks from the cache and storing the block in the cache, if the total size of the evictable blocks is greater than or equal to the size of the block, and activating a cache throttle, if the total size of the evictable blocks is less than the size of the block.

Abstract: A dynamic prediction is made whether a load instruction will miss a cache. Data is prefetched for the load instruction when a cache miss is predicted. Thus, the prefetch is only performed if a trigger event correlated with a cache miss for that load instruction is detected. This selective execution of the prefetches for a particular load instruction improves processor utilization and performance.

Abstract: A system and method of allocating contiguous real memory in a data processing system. A memory controller within system memory receives a request from a data processing system component for a contiguous block of memory during operation of the data processing system. In response to receiving the request, the memory controller selects a candidate contiguous block of memory. Then, after temporarily restricting access to the candidate contiguous block of memory, the memory controller identifies a set of frames currently in use within the candidate contiguous block of memory, relocates the set of frames, and allocates the candidate block of memory for exclusive use by the requesting data processing component. The allocation of contiguous real memory occurs dynamically during the operation of the data processing system.

Abstract: An apparatus, system, and method for replicating a snapshot volume in a first storage system to a second storage system includes mapping information corresponding to data in the first storage system that is transferred from the first storage system to the second storage system so that a file system in the second storage system can mount the data after replication. Replication of the snapshot volume can be accomplished using a remote copy mechanism. The snapshot volume can be obtained from a primary source volume P-VOL and a differential source volume D-VOL. If the corresponding destination volumes are not known, a search is conducted to locate appropriate volumes in the second storage system. Mapping information regarding these destination volumes is utilized to enable the file system in the second storage system to mount the replicated snapshot volume.

Abstract: A system and method of allocating contiguous real memory in a data processing system. A memory controller within system memory receives a request from a data processing system component for a contiguous block of memory during operation of the data processing system. In response to receiving the request, the memory controller selects a candidate contiguous block of memory. Then, after temporarily restricting access to the candidate contiguous block of memory, the memory controller identifies a set of frames currently in use within the candidate contiguous block of memory, relocates the set of frames, and allocates the candidate block of memory for exclusive use by the requesting data processing component. The allocation of contiguous real memory occurs dynamically during the operation of the data processing system.

Abstract: A method, apparatus, and computer instructions are provided for storage provisioning automation in a data center. A storage manager is provided in the present invention to facilitate end-to-end deployment of storage resources for a server in the data center. The storage manager includes functionalities of a volume manager, file system, and physical volumes. In addition, a hierarchical structure is provided by the present invention to specify configuration data for a volume container. The hierarchical structure includes volume container settings, which includes physical volume settings and logical volume settings linked through data partition settings. For SAN volumes, storage multipath settings and data path settings are included in the structure. File system settings and mounting settings are also included to mount a file system once it is created.

Abstract: A system and method of allocating contiguous real memory in a data processing system. A memory controller within system memory receives a request from a data processing system component for a contiguous block of memory during operation of the data processing system. In response to receiving the request, the memory controller selects a candidate contiguous block of memory. Then, after temporarily restricting access to the candidate contiguous block of memory, the memory controller identifies a set of frames currently in use within the candidate contiguous block of memory, relocates the set of frames, and allocates the candidate block of memory for exclusive use by the requesting data processing component. The allocation of contiguous real memory occurs dynamically during the operation of the data processing system.

Abstract: A volume matrix is established including host devices on a host computer and virtual devices and logical devices on a data storage system. Each host device/virtual device (H/V) pair has a user-visible primary address range to serve as a primary H/V pair on a primary path for a logical device, and selected H/V pairs also have one or more user-hidden secondary address ranges to serve as secondary H/V pairs on secondary paths for other logical devices. The host computer directs storage requests to either the primary path or a secondary path to a target logical device based on expected performance criteria, and if a secondary path is used then the address is translated to the correct secondary address range. The data storage system performs the storage request on the target logical device after determining whether the request was received on the primary path or a secondary path, in which case the storage address is further translated to an address range of the target logical device.

Abstract: A method, apparatus, and computer instructions are provided for storage provisioning automation in a data center. A storage manager is provided in the present invention to facilitate end-to-end deployment of storage resources for a server in the data center. The storage manager includes functionalities of a volume manager, file system, and physical volumes. In addition, a hierarchical structure is provided by the present invention to specify configuration data for a volume container. The hierarchical structure includes volume container settings, which includes physical volume settings and logical volume settings linked through data partition settings. For SAN volumes, storage multipath settings and data path settings are included in the structure. File system settings and mounting settings are also included to mount a file system once it is created.

Abstract: A computer system is provided with a collection section for collecting load information related to an application server and a storage subsystem, a transmission section for predicting a write processing property based on the load information collected by the collection section and for transmitting the write processing property to the storage subsystem, and a write control section for controlling a write processing to a hard disk drive in the storage subsystem based on the write processing property transmitted by the transmission section. A target of the writable cache amount is set so that a write processing amount from a cache of the storage subsystem to the hard disk drive is averaged in terms of time, and the write processing to the hard disk drive is performed to satisfy the target of the writable cache amount.