Abstract: Aspects of the current subject matter are directed to an approach in which a parallel load operation of file ID mapping containers is accomplished at start and/or restart of a database system. Parallel load operation of file ID mapping and/or large binary object (LOB) file ID mapping is done among a plurality of scanning engines into a plurality of data buffers that are associated with each of the plurality of scanning engines. Each scanning engine operates on a certain path of a page chain of a page structure including the mapping, causing the page chain to be split among scanning engines to process maps. Contents of the data buffers are pushed to mapping engines via a queue. The mapping engines load the file ID mapping and the LOB file ID mapping into maps for in-system access.

Abstract: A database system receives a mass insert operation command specifying a plurality of entries. Thereafter, the entries are iteratively inserted into a plurality of preliminary pages associated with a container provided by a persistence layer of the database system. Thereafter, the preliminary pages are registered to the container once they are full.

Abstract: Recovery of an in-memory database is initiated. Thereafter, pages for recovery having a size equal to or below a pre-defined threshold are copied to a superblock. For each copied page, encryption information is added to a superblock control block for the superblock. The copied pages are encrypted within the superblock using the corresponding encryption information added to the super block control block. The superblock is then flushed from memory (e.g., main memory, etc.) of the database to physical persistence.

Abstract: Checking of a database snapshot of an active database is initiated. Thereafter, an anchor page associated with a most recent snapshot that links to a restart page is read. Subsequently, the linked restart page is read. It is then initially determined, based on the reading of the anchor page and the restart page, whether the snapshot is accurate. If it is initially determined that the snapshot is not accurate, the anchor page and the restart page are re-read until a final determination is made that whether the snapshot is accurate. Alternatively, if not is initially determined that the snapshot is accurate, then data is provided (e.g., displayed, loaded into memory, transmitted to a remote computing system, stored in physical persistence, etc.) that indicates that the snapshot is accurate.

Abstract: A request is received for a first non-exclusive lock to read a page in a database. Thereafter, execution of the at least one non-exclusive lock is initiated. Later, a request for an exclusive lock to modify the page in the database is received. Subsequently, a request is received for a second non-exclusive lock. In response, an amount of time to finish the first request and the second request is estimated. The second non-exclusive lock is allowed to execute in parallel to the first non-exclusive if the determined amount of time to finish the second non-exclusive lock is less than an estimated amount of time needed by the first non-exclusive lock. Alternatively, execution of the second non-exclusive lock is delayed to after the execution of the exclusive lock if the determined amount of time to finish the second non-exclusive lock is greater than an amount of time needed by the first non-exclusive lock.

Abstract: Aspects of the current subject matter are directed to an approach in which a parallel load operation of file ID mapping containers is accomplished at start and/or restart of a database system. Parallel load operation of file ID mapping and/or large binary object (LOB) file ID mapping is done among a plurality of scanning engines into a plurality of data buffers that are associated with each of the plurality of scanning engines. Each scanning engine operates on a certain path of a page chain of a page structure including the mapping, causing the page chain to be split among scanning engines to process maps. Contents of the data buffers are pushed to mapping engines via a queue. The mapping engines load the file ID mapping and the LOB file ID mapping into maps for in-system access.

Abstract: A temporary page is allocated in which pages are loaded into main memory and having associated physical disk storage. The temporary page is also flagged as being temporary. Subsequently, a savepoint is initiated for the database so that, during the savepoint, the temporary page can be modified without acquiring a consistent change while preventing other non-temporary pages from being modified. Later, the savepoint can be finalized to enable the database to be rolled back to a point in time corresponding to the savepoint as part of a recovery process.

Abstract: Recovery of an in-memory database is initiated. Thereafter, pages for recovery having a size equal to or below a pre-defined threshold are copied to a superblock. For each copied page, encryption information is added to a superblock control block for the superblock. The copied pages are encrypted within the superblock using the corresponding encryption information added to the super block control block. The superblock is then flushed from memory (e.g., main memory, etc.) of the database to physical persistence.

Abstract: A database receives pages that are piped from backup media with each of the pages having a corresponding savepoint version. At least a portion of the pages are then flagged as being from recovery. The savepoint versions for the pages are maintained if they have a flag. A single checksum is then calculated for each page to confirm integrity. Each page is then loaded into memory of the database after it is confirming the corresponding calculated single checksum. Related apparatus, systems, techniques and articles are also described.

Abstract: Execution of an exclusive lock of a page in a database is initiated. Thereafter, subsequent to the initiation of the execution of the exclusive lock, at least one non-exclusive lock for the page in the database is received. The execution of the exclusive lock is selectively timed out based on at least one savepoint statistic. While the exclusive lock is timed out, at least one of the received non-exclusive locks is executed. Further, the exclusive lock can be restarted after the execution of the at least one of the received non-exclusive locks.

Abstract: Systems and methods are described herein for system critical phase lock job inhibitors. Acquisition of a consistent change exclusive lock is initiated. A job request having a scope object is received. Execution of the job request and generation of a replacement job associated with the job request is prohibited based on the scope object indicating that the job requires consistent change access during the consistent change exclusive lock.

Abstract: Physical block numbers are assigned to pages loaded into memory of an in-memory database. Thereafter, pages having a same size are distributed to one of a plurality of helper threads executing in parallel for processing if such pages having consecutive physical block numbers. Each of these helper threads can have a corresponding small page buffer. Contents of the respective small page buffers are later flushed to physical disk persistence when such small page buffers are full.

Abstract: Systems and methods are described herein for job execution using system critical threads. An in-memory database system having pages loaded into a memory and having associated physical disk storage generates a safety critical thread pool. The safety critical thread pool has one or more safety critical threads associated with flushing the pages to the physical disk storage. Execution of the one or more safety critical threads is initiated within the safety critical thread pool. A job request to access data stored within the physical disk storage is received. Utilization levels of the one or more safety critical threads are monitored. Execution of the job request is permitted based on the utilization levels associated with the one or more safety critical threads.

Abstract: Loading of a page into memory of an in-memory database system is initiated. Thereafter, a new page size for the page in memory is allocated corresponding to a greater of a current page size and an intended page size. Later, the page is loaded into the allocated memory so that a consistent change can be opened. Content within the page is reorganized according to the new page size followed by the consistent change being closed.

Abstract: Resources are loaded into a resource container in an in-memory database system in which pages are loaded into memory and having associated physical disk storage. Each resource is assigned a new time stamp when such resource is loaded into the resource container. At least some of the references are subsequently accessed and time stamps associated with these accesses resources are selectively updated based on the type of access. These time stamps are later used to evict least recently used resources (as indicated by their time stamps) from the resource container.

Abstract: Data records of a data set can be stored in multiple main part fragments retained in on-disk storage. Each fragment can include a number of data records that is equal to or less than a defined maximum fragment size. Using a compression that is optimized for each fragment, each fragment can be compressed. After reading at least one of the fragments into main system memory from the on-disk storage, an operation can be performed on the fragment or fragments while the in the main system memory.

Abstract: A temporary page is allocated in which pages are loaded into main memory and having associated physical disk storage. The temporary page is also flagged as being temporary. Subsequently, a savepoint is initiated for the database so that, during the savepoint, the temporary page can be modified without acquiring a consistent change while preventing other non-temporary pages from being modified. Later, the savepoint can be finalized to enable the database to be rolled back to a point in time corresponding to the savepoint as part of a recovery process.

Abstract: A database system receives a mass insert operation command specifying a plurality of entries. Thereafter, the entries are iteratively inserted into a plurality of preliminary pages associated with a container provided by a persistence layer of the database system. Thereafter, the preliminary pages are registered to the container once they are full.

Abstract: Physical block numbers are assigned to pages loaded into memory of an in-memory database. Thereafter, pages having a same size are distributed to one of a plurality of helper threads executing in parallel for processing if such pages having consecutive physical block numbers. Each of these helper threads can have a corresponding small page buffer. Contents of the respective small page buffers are later flushed to physical disk persistence when such small page buffers are full.

Abstract: Recovery of an in-memory database is initiated. Thereafter, pages for recovery having a size equal to or below a pre-defined threshold are copied to a superblock. For each copied page, encryption information is added to a superblock control block for the superblock. The copied pages are encrypted within the superblock using the corresponding encryption information added to the super block control block. The superblock is then flushed from memory (e.g., main memory, etc.) of the database to physical persistence.