摘要:
A dual cluster storage server maintains track control blocks (TCBs) in a data structure to describe the data stored in cache in corresponding track images or segments. Following a cluster failure and reboot, the surviving cluster uses the TCBs to rebuild data structures such as a scatter table, which is a hash table that identifies a location of a track image, and a least recently used (LRU)/most recently used (MRU) list for the track images. This allows the cache data to be recovered. The TCBs describe whether the data in the track images is modified and valid, and describe forward and backward pointers for the data in the LRU/MRU lists. A separate non-volatile memory that is updated as the track images are updated is used to verify the integrity of the TCBs.
摘要:
An improved storage controller and method for storing and recovering data are disclosed. The storage controller includes a first cluster for directing data from a host computer to a storage device and a second cluster for directing data from a host computer to a storage device. A first cache memory is connected to the first cluster and a second cache memory is connected to the second cluster. A first preserved area of memory is connected to the first cluster and a second preserved area of memory is connected to the second cluster. Data is directed to the first cache and backed up to the second preserved area in a normal operating mode. Similarly, data is directed to the second cache and backed up to the first preserved area in the normal operating mode. In the event of a power failure or comparable event, data from the first and second preserved areas are transferred to, and stored on, a first storage device. Additionally, data from the first and second preserved areas are transferred to, and stored on, a second storage device. Thus, upon resumption of normal operation, if one of the clusters subsequently fails to resume normal operations, data from the failed cluster is available through the operating cluster.
摘要:
Disclosed are a storage controller, and a method of operating a storage controller, for interfacing between host systems and a storage devices system. The storage controller includes a first cluster including a first processor and a first cache, and a second cluster including a second processor and a second cache. The method comprises the step of directing data from the host systems through first and second data paths to the storage system. The first processor and cache are associated with the first data path, and the second processor and cache are associated with the second data path. Under one set of conditions, the controller enters a failover mode, wherein data directed to the first data path are routed to the second data path. Under another set of conditions, the controller deconfigures the first cache without entering the failover mode.
摘要:
A method to rebuild an NVS image is disclosed. The method provides information to a first cluster of an information storage and retrieval system, and writes that information to a non-volatile storage device disposed in a second cluster. Upon losing utility power to all or part of the information storage and retrieval system, the method provides back-up power to a processor and a data cache, and determines if the information written to the second non-volatile storage device is accessible. If the information written to the second non-volatile storage device is accessible, then the method copies the image of that second non-volatile storage device to an external storage device. If the information written to said second non-volatile storage device is not accessible, then the method creates a virtual NVS image using the information disposed in a local data cache, and copies that virtual NVS image to an external storage device.
摘要:
Disclosed are a storage controller, and a method of operating a storage controller, for interfacing between host systems and a storage devices system. The storage controller includes a first cluster including a first processor and a first cache, and a second cluster including a second processor and a second cache. The method comprises the step of directing data from the host systems through first and second data paths to the storage system. The first processor and cache are associated with the first data path, and the second processor and cache are associated with the second data path. Under one set of conditions, the controller enters a failover mode, wherein data directed to the first data path are routed to the second data path. Under another set of conditions, the controller deconfigures the first cache without entering the failover mode.
摘要:
Mechanisms are provided for extending cache for an external storage system into individual servers. Certain servers may have cards with cache in the form of dynamic random access memory (DRAM) and non-volatile storage, such as flash memory or solid-state drives (SSDs), which may be viewed as actual extensions of the external storage system. In this way, the storage system is distributed across the storage area network (SAN) into various servers. Several new semantics are used in communication between the cards and the storage system to keep the read caches coherent.
摘要:
A mold assembly for insert-molding a heterogeneous object includes an upper mold and a lower mold. The upper mold includes a cavity for accommodating an insert object. The lower mold includes a rigid body and a resilient contact member for resting the insert object. The resilient contact member absorbs dimensional variations of the insert object during the insert molding process.
摘要:
Input/output (I/O) activity in the multiple tier storage system is monitored to collect statistical information. The statistical information is recurrently transformed into an exponential moving average (EMA) of the I/O activity having a predefined smoothing factor. Data portions in the multiple tier storage system are sorted into buckets of varying temperatures corresponding to the EMA. At least one data migration plan is recurrently generated for matching the sorted data portions to at least one of an available plurality of storage device classes. One data portion sorted into a higher temperature bucket is matched with a higher performance storage device class of the available plurality of storage device classes than another data portion sorted into a lower temperature bucket.
摘要:
Provided are a computer program product, system and method for managing Input/Output (I/O) requests to a storage device. A write request is received having write data for a logical address in the storage device. A determination is made as to whether preserve mode is enabled. A first entry is located in a volume control table for the logical address indicating a version number of the data in the storage device for the logical address and a first physical location in the storage device having the data for the logical address. The write data is written to a second physical location in the storage device. A second entry is added to the volume control table for the logical address to write in response to determining that the preserve mode is enabled. In response to determining that the preserve mode is enabled, the volume control table is updated to have one of the first and second entry for the logical address point to the second physical location and have the version number indicate a current version and to have the first or second entry not indicating the current version to indicate the first physical location and the version number indicate a previous version.
摘要:
Provided are a method, system, and program for an adaptor to read and write to system memory. A plurality of blocks of data to write to storage are received at an adaptor. The blocks of data are added to a buffer in the adaptor. A determination is made of pages in a memory device and I/O requests are generated to write the blocks in the buffer to the determined pages, wherein two I/O requests are generated to write to one block split between two pages in the memory device. The adaptor executes the generated I/O requests to write the blocks in the buffer to the determined pages in the memory device.