Described are methods, systems and computer readable media for dynamic updating of query result displays.

Described are methods, systems and computer readable media for performance logging of complex query operations.

Described are methods, systems and computer readable media for data source refreshing.

A method for to manage concurrent access to a shared resource in a distributed computing environment. A reference counter counts is incremented for every use of an object subtype in a session and decremented for every release of an object subtype in a session. A session counter is incremented upon the first instance of fetching an object type into a session cache and decremented upon having no instances of the object type in use in the session. When both the reference counter and the session counter are zero, the object type may be removed from the cache.

According to one embodiment, a memory system manages a plurality of management tables corresponding to a plurality of first blocks in a nonvolatile memory. Each management table includes a plurality of reference counts corresponding to a plurality of data in a corresponding first block. The memory system copies a set of data included in a copy-source block for garbage collection and corresponding respectively to reference counts belonging to a first reference count range to a first copy-destination block, and copies a set of data included in the copy-source block and corresponding respectively to reference counts belonging to a second reference count range having a lower limit higher than an upper limit of the first reference count range to a second copy-destination block.

Systems, methods, and computer readable storage mediums for optimistically managing compressed data in a storage system. When possible, multiple input blocks are compressed into a buffer and stored in a single physical block on a storage device. The metadata of the multiple input blocks can be managed separately. A fingerprint of the compressed buffer can be generated and used as an index to the single physical block. Alternatively, fingerprints of the uncompressed input blocks can be generated, and reference counts can be maintained to track the number of input blocks which reference the compressed buffer. In some embodiments the physical block is associated with a zone represented by a virtual construct, wherein the zone is dynamically mapped to underlying storage of the zoned storage system.

A controller controls an operation of a semiconductor memory device. The controller includes a request analyzer, a storage, and a garbage collection controller. The request analyzer generates invalid data information, based on an erase request received from a host. The storage stores a garbage collection reference table representing memory blocks excluded from selection as a victim block on which a garbage collection operation is to be performed, based on the invalid data information. The garbage collection controller controls the garbage collection operation on the semiconductor memory device, based on exclusion block information generated according to the garbage collection reference table.

An operation method of a controller, comprising: selecting a target super block, on which garbage collection (GC) is to be performed, among a plurality of super blocks which are completely programmed, based on a first valid page count of each of the super blocks when a determination to perform GC is made; selecting a first target block among a plurality of memory blocks in the target super block based on a second valid-page decrease amount of each of the memory blocks; and performing a first copy operation on valid pages in the first target block.

During execution of garbage collection, an application receives a first request to overwrite a reference field of an object, the object comprising a first reference and the first request comprising a memory address at which the reference field is stored, and a second reference to be written to the reference field. Responsive to receiving the first request, the system determines a current remembered set phase, and loads the first reference. The application determines that remembered set metadata of the first reference does not match the current remembered set phase. Responsive to that determination, the application adds an entry to a remembered set data structure, modifies the second reference to include the current remembered set phase as the remembered set metadata, and stores the modified second reference to the reference field. In subsequent writes to the reference field, the application refrains from adding to the remembered set data structure.

Described are methods, systems and computer readable media for providing a current row position query language construct and array processing query language constructs and associated processing.