Patent application number | Description | Published |
20080244210 | ELIMINATING FRAGMENTATION WITH BUDDY-TREE ALLOCATION - This disclosure describes solutions for reducing the amount of fragmentation on a computer memory device, such as a hard disk, random access memory device, and/or the like. In an aspect, this disclosure describes systems, methods and software for allocating storage space for variable-sized data chunks in a fashion that reduces or eliminates the need for periodic de-fragmentation of the memory device. In another aspect, this disclosure describes solutions that provide for the dynamic re-allocation of existing data blocks on the memory device to provide contiguous available space that can be allocated for new data blocks. | 10-02-2008 |
20080281954 | Capability requirements for group membership - A method and apparatus for adding a node to a group of nodes is provided. Group capability data is stored in volatile memory of a group manager for a group. The group capability data identifies capability requirements for members of the group. The group manager provides notification services for members of the group. A request to add a particular node to a group is received. In response to receiving the request, a determination is made as to whether the particular node satisfies the capability requirements identified by the group capability data. Upon determining that the particular node does satisfy the capability requirements identified by the group capability data, the particular node is added to the group. The capability requirements for members of a group may initially be based on the capabilities of the first node that is added to a group. | 11-13-2008 |
20090006797 | FENCING USING A HIERARCHICAL RELATIONSHIP - A method and apparatus for processing a write request at a storage device is provided. A write request that identifies a sender of the write request is received at a storage device. The write request is examined to determine the identity of the sender. A determination is made as to whether, within a hierarchical relationship, the sender is subordinate to any entity that has been designated as being unable to perform write requests at the storage device. Upon determining that (a) the sender is not subordinate to any entity that has been designated as being unable to perform write requests at the storage device, and (b) the sender has not been designated as being unable to perform write requests at the storage device, the sender is allowed to write to the storage device. Thereafter, the write request from the sender may be performed at the storage device. | 01-01-2009 |
20100125842 | EFFICIENT VOLUME MANAGER HOT SWAPPING - Methods of hot-swapping a logical volume manager (LVM) and updating an associated extent map are presented. Methods for migrating a virtual machine running an application using an LVM from one physical machine to another physical machine are also presented. The LVM can be used by a database application or other applications in a single-node or multi-node environment. The LVM is shut down, version numbers for each segment of its associated extent map are saved, and a new LVM is started. The new LVM's extent map is compared with the old extent map, and segments in the LVM which have changed are selectively updated. | 05-20-2010 |
20110106774 | Bootstrapping Server Using Configuration File Stored In Server-Managed Storage - A method and apparatus for booting a clustered management system is provided where the configuration information required to boot the system is stored within the system itself. The techniques cope with several issues including finding the configuration data on the physical disk before the logical disk system is established, coping with replicated copies of configuration data, network partitions and disk drive failures that may prevent a booting node to have perfect knowledge of the state of the entire system, and active nodes modifying or moving configuration data while the booting node is searching for a consistent, correct copy of configuration data. | 05-05-2011 |
20120159094 | ASSIGNING READ REQUESTS BASED ON BUSYNESS OF DEVICES - Techniques are provided for assigning read requests to storage devices in a manner that reduces the likelihood that any storage device will become overloaded or underutilized. Specifically, a read-request handler assigns read requests that are directed to each particular item among the storage devices that have copies of the item based on how busy each of those storage devices is. Consequently, even though certain storage devices may have copies of the same item, there may be times during which one storage device is assigned a disproportionate number of the reads of the item because the other storage device is busy with read requests for other items, and there may be other times during which other storage device is assigned a disproportionate number of the reads of the item because the one storage device is busy with read request for other items. Various techniques for estimating the busyness of storage devices are provided, including fraction-based estimates, interval-based estimates, and the response-time-based estimates. Techniques for smoothing those estimates, and for handicapping devices, are also provided. | 06-21-2012 |
20130055018 | DETECTION OF LOGICAL CORRUPTION IN PERSISTENT STORAGE AND AUTOMATIC RECOVERY THEREFROM - A method, system, and computer program product for restoring blocks of data stored at a corrupted data site using two or more mirror sites. The method commences by receiving a trigger event from a component within an application server environment where the trigger event indicates detection of a corrupted data site. The trigger is classified into at least one of a plurality of trigger event types, which trigger event type signals further processing for retrieving from at least two mirror sites, a first stored data block and a second stored data block corresponding to the same logical block identifier from the first mirror site. The retrieved blocks are compared to determine a match value, and when the match value is greater than a confidence threshold, then writing good data to the corrupted data site before performing consistency checks on blocks in physical or logical proximity to the corrupted data site. | 02-28-2013 |
20130097374 | EFFICIENT VOLUME MANAGER HOT SWAPPING - A method of updating an extent map is described. The method includes providing in a memory an instance of a first version of the extent map, wherein the instance is referenced by an application. The extent map include entries. The method further includes storing, at each extent map entry, an offset from the beginning of a physical drive which is identified within said each extent map entry, providing a second version of the extent map, comparing the first version of the extent map with the second version of the extent map, in response to the comparing, determining that is at least on segment in the second version of the extent map that is different from a corresponding at least one segment in the first version of the extent map. | 04-18-2013 |
20140250323 | DETECTION OF LOGICAL CORRUPTION IN PERSISTENT STORAGE AND AUTOMATIC RECOVERY THEREFROM - A method, system, and computer program product for restoring blocks of data stored at a corrupted data site using two or more mirror sites. The method commences by receiving a trigger event from a component within an application server environment where the trigger event indicates detection of a corrupted data site. The trigger is classified into at least one of a plurality of trigger event types, which trigger event type signals further processing for retrieving from at least two mirror sites, a first stored data block and a second stored data block corresponding to the same logical block identifier from the first mirror site. The retrieved blocks are compared to determine a match value, and when the match value is greater than a confidence threshold, then writing good data to the corrupted data site before performing consistency checks on blocks in physical or logical proximity to the corrupted data site. | 09-04-2014 |