Abstract: A computing device is configured to allocate memory for exclusive use of an execution entity from both a shared memory area and a private memory area of the device. Specifically, the shared memory area is configured with a united memory pool (UMP) component. The UMP component is configured to provide portions of huge page-based memory to execution entities for exclusive use of the execution entities. Memory granules that are allocated to the UMP component are divided into smaller memory chunks (which are smaller than a huge page), each of which can be allocated for exclusive use of an execution entity. These memory chunks are mapped to virtual address spaces of the assigned execution entities. Because memory granules can be allocated to, and deallocated from, the UMP component at run-time, the amount of memory that is available for private data generated by execution entities is able to be dynamically adjusted.

Abstract: Disclosed is an improved approach to access the contents of database file system. The contents of the database file system can be acquired and stored in a directory buffer. A parallel tree structure is used to retrieve directory contents quickly and in a consistent fashion.

Abstract: Herein are resource-constrained techniques that plan ahead for resiliently moving pluggable databases between container databases after a failure in a high-availability database cluster. In an embodiment that has a database cluster that hierarchically contains many pluggable databases in many container databases in many virtual machines, a computer identifies many alternative placements that respectively assign each pluggable database instance (PDB) to a respective container database management system (CDBMS). For each alternative placement, a respective placement score is calculated based on the PDBs and the CDBMSs. Based on the placement scores of the alternative placements, a particular placement is selected with a best placement score that indicates optimal resilience for accommodating adversity such as failover and overcrowding.

Abstract: Herein are resource-constrained techniques that plan ahead for resiliently moving pluggable databases between container databases after a failure in a high-availability database cluster. In an embodiment, a computer identifies many alternative placements that respectively assign each pluggable database to a respective container database. For each alternative placement, a respective resilience score is calculated for each pluggable database that is based on the container database of the pluggable database. Based on the resilience scores of the pluggable databases for the alternative placements, a particular placement is selected as an optimal placement that would maximize utilization of computer resources, minimize database latencies, maximize system throughput, and maximize the ability of the database cluster to avoid a service outage.

Abstract: Techniques are provided for block-level fail atomicity on byte-level non-volatile media. In one technique, an offset table and application data that stores content of a file are stored for a file. The offset table includes multiple entries, each entry being associated with a different offset value and storing a logical block address (LBA) that references a location in the application data. In response to receiving a request, that includes an input buffer and an offset value, to update the file: (a) an entry, in the offset table, that corresponds to the offset value and comprises a first LBA is identified; (b) a second LBA that is considered free is identified; (c) the second LBA is replaced with the first LBA; (d) the input buffer is written to a location, in the application data, that the second LBA references; and (e) the second LBA is added in the entry.

Abstract: Techniques are provided for block-level fail atomicity on byte-level non-volatile media. In one technique, an offset table and application data that stores content of a file are stored for a file. The offset table includes multiple entries, each entry being associated with a different offset value and storing a logical block address (LBA) that references a location in the application data. In response to receiving a request, that includes an input buffer and an offset value, to update the file: (a) an entry, in the offset table, that corresponds to the offset value and comprises a first LBA is identified; (b) a second LBA that is considered free is identified; (c) the second LBA is replaced with the first LBA; (d) the input buffer is written to a location, in the application data, that the second LBA references; and (e) the second LBA is added in the entry.

Abstract: A computing device is configured to allocate memory for exclusive use of an execution entity from both a shared memory area and a private memory area of the device. Specifically, the shared memory area is configured with a united memory pool (UMP) component. The UMP component is configured to provide portions of huge page-based memory to execution entities for exclusive use of the execution entities. Memory granules that are allocated to the UMP component are divided into smaller memory chunks (which are smaller than a huge page), each of which can be allocated for exclusive use of an execution entity. These memory chunks are mapped to virtual address spaces of the assigned execution entities. Because memory granules can be allocated to, and deallocated from, the UMP component at run-time, the amount of memory that is available for private data generated by execution entities is able to be dynamically adjusted.

Abstract: Disclosed is an improved approach to access the contents of database file system. The contents of the database file system can be acquired and stored in a directory buffer. A parallel tree structure is used to retrieve directory contents quickly and in a consistent fashion.

Abstract: Herein are resource-constrained techniques that plan ahead for resiliently moving pluggable databases between container databases after a failure in a high-availability database cluster. In an embodiment that has a database cluster that hierarchically contains many pluggable databases in many container databases in many virtual machines, a computer identifies many alternative placements that respectively assign each pluggable database instance (PDB) to a respective container database management system (CDBMS). For each alternative placement, a respective placement score is calculated based on the PDBs and the CDBMSs. Based on the placement scores of the alternative placements, a particular placement is selected with a best placement score that indicates optimal resilience for accommodating adversity such as failover and overcrowding.

Abstract: A computer program product, system, and computer implemented method for rapid database restoration using a database restore and recovery process that leverages one or more sparse data files and/or blocks by restoring one or more sparse data files and/or blocks and providing a mechanism to redirect requests to the one or more sparse data files and/or blocks to a backup copy of the actual data files and/or blocks and a process to populate the one or more sparse data files and/or blocks while the database is operational for servicing user requests. The approach includes the creation and population of one or more sparse data files and/or blocks, a redirection mechanism to service read operations where necessary, and a process to restore the data to one or more sparse data files and/or blocks over time, while the database maintains operability.

Abstract: Herein are resource-constrained techniques that plan ahead for resiliently moving pluggable databases between container databases after a failure in a high-availability database cluster. In an embodiment, a computer identifies many alternative placements that respectively assign each pluggable database to a respective container database. For each alternative placement, a respective resilience score is calculated for each pluggable database that is based on the container database of the pluggable database. Based on the resilience scores of the pluggable databases for the alternative placements, a particular placement is selected as an optimal placement that would maximize utilization of computer resources, minimize database latencies, maximize system throughput, and maximize the ability of the database cluster to avoid a service outage.

Abstract: Techniques are described herein for isolating a network stack in a multitenant container DBMS. A first and second pluggable database are established within a container database. A first network stack is assigned to the first pluggable database and a second network stack is assigned to the second pluggable database. A request is received to connect to the first pluggable database and a connection is established to the first pluggable database using the first network stack. A request is received to connect to the second pluggable database and a connection is established to the second pluggable database using the second network stack.

Abstract: Techniques are described herein for isolating runtime environments in a multitenant container DBMS. A CDB may contain a database dictionary that defines a plurality of pluggable databases and a respective database nest for each pluggable database. Each respective database nest of said each pluggable database is associated with different operating system privileges. When database sessions are established on a container DBMS, each database session is given access to a pluggable database by attaching the respective database nest of the pluggable database to each database session.

Abstract: Techniques are described herein for cloning a database. According to some embodiments, a database server receives a request to clone a source database. In response to receiving the request, the database server retrieves a set of one or more storage credentials for a set of one or more respective storage systems on which a set of files of the source database are stored. The set of storage credentials grant permission to the database server to create snapshot copies on the set of storage systems. The database server generates, for a target database using the set of storage credentials, a snapshot copy of each respective file in the set of files of the source database. The snapshot copy of the respective file points to the same set of one or more data blocks as the respective file until at least one of the data blocks is modified.

Abstract: A method and apparatus for intelligent network resource manager for distributed computing systems is provided. A first priority is assigned to a first virtual channel set that includes at least two virtual channels of a plurality of virtual channels associated with a physical communication channel. A second priority is assigned to a second virtual channel set that includes at least one virtual channel of the plurality of virtual channels. The first virtual channel set has more virtual channels than the second virtual channel set. Outbound messages of the first priority are directed to virtual channels of the first virtual channel set. Outbound messages of the second priority are directed to virtual channels of the second virtual channel set. The virtual channels are processed in a round-robin order, where processing includes sending the outbound messages over the physical communication channel.

Abstract: A method and apparatus for intelligent network resource manager for distributed computing systems is provided. A first priority is assigned to a first virtual channel set that includes at least two virtual channels of a plurality of virtual channels associated with a physical communication channel. A second priority is assigned to a second virtual channel set that includes at least one virtual channel of the plurality of virtual channels. The first virtual channel set has more virtual channels than the second virtual channel set. Outbound messages of the first priority are directed to virtual channels of the first virtual channel set. Outbound messages of the second priority are directed to virtual channels of the second virtual channel set. The virtual channels are processed in a round-robin order, where processing includes sending the outbound messages over the physical communication channel.

Abstract: Techniques are described herein for isolating runtime environments in a multitenant container DBMS. A CDB may contain a database dictionary that defines a plurality of pluggable databases and a respective database nest for each pluggable database. Each respective database nest of said each pluggable database is associated with different operating system privileges. When database sessions are established on a container DBMS, each database session is given access to a pluggable database by attaching the respective database nest of the pluggable database to each database session.

Abstract: Techniques are described herein for isolating a network stack in a multitenant container DBMS. A first and second pluggable database are established within a container database. A first network stack is assigned to the first pluggable database and a second network stack is assigned to the second pluggable database. A request is received to connect to the first pluggable database and a connection is established to the first pluggable database using the first network stack. A request is received to connect to the second pluggable database and a connection is established to the second pluggable database using the second network stack.

Abstract: A method and apparatus for intelligent network resource manager for distributed computing systems is provided. A first priority is assigned to a first virtual channel set that includes at least two virtual channels of a plurality of virtual channels associated with a physical communication channel. A second priority is assigned to a second virtual channel set that includes at least one virtual channel of the plurality of virtual channels. The first virtual channel set has more virtual channels than the second virtual channel set. Outbound messages of the first priority are directed to virtual channels of the first virtual channel set. Outbound messages of the second priority are directed to virtual channels of the second virtual channel set. The virtual channels are processed in a round-robin order, where processing includes sending the outbound messages over the physical communication channel.

Abstract: Described herein is a quenching system comprising a spinneret to spin molten polymer, a quench stack disposed operatively below the spinneret and the flow communication with the spinneret, a first means to provide a first stream of ambient air to provide partially-quenched solidified fibers of the molten polymer spun through the spinneret, at a solidification temperature and a second means to provide a second stream of conditioned air at a below-ambient temperature for further quenching the partially quenched solidified fibers, wherein the second stream of the conditioned air is provided through an adapter placed operatively below a region where the molten polymer solidifies partially.