Apple Inc.

Other

Benjamin C Trumbull

Andreas W Wendker

Ronald Dennis Lue-Sang

Christopher M Hanson

Melissa Turner

Bill Bumgarner

Stephen E Miner

Russell Alexader Blaine

Adam C Swift

Lionel Divyang Desai

Benjamin H Nham

Dominic Benjamin Giampaolo

Dallas Blake De Atley

Umesh Suresh Vaishampayan

Curtis Galloway

Matthew G Watson

Matthew Reda

Timothy Paul Marsland

Kari E Christianson

Nicholas W Gillett

Nicholas William Colby Gillett

Techniques are disclosed relating to virtual memory page reclamation policies. In some embodiments, an operating system of a computing device implements, during a first operating mode, a first page reclamation policy for pages corresponding to user processes and non-user processes. The computing device may then enter a second operating mode upon detecting some indication of user inactivity. The operating system may then implement, during the second operating mode, a second page reclamation policy for pages corresponding to user processes and non-user processes, where the second page reclamation policy prioritizes, relative to the first page reclamation policy, eviction of pages corresponding to non-user processes.

Memory page reclamation in a user idle mode

According to one embodiment, it is determined whether data stored in a compressor pool exceeds a first predetermined threshold, the compressor pool being a fixed-size memory pool maintained in a kernel of an operating system. The compressor pool stores a plurality of compressed memory pages, each memory page storing compressed data pages that can be paged out to or paged in from a persistent storage device. The compressed memory pages are associated with a plurality of processes. A memory consumption reduction action is performed to reduce memory usage, including terminating at least one of the processes to reclaim a memory space occupied by the process, in response to determining that the data stored in the compressor pool exceeds the first predetermined threshold.

Method and apparatus for managing kernel memory of data processing systems

An operating system of a data processing system receives a request from a first process to acquire an exclusive lock for accessing a resource of the data processing system. A second priority of a second process is increased to reduce total execution time. The second process is currently in possession of the exclusive lock for performing a transactional operation with the resource. The second priority was lower than a first priority of the first process. The operating system notifies the second process to indicate that another process is waiting for the exclusive lock to allow the second process to complete or roll back the transactional operation and to release the exclusive lock thereafter.

Adaptive handling of priority inversions using transactions

Methods and apparatus are provided in which applications that run on different devices can be upgraded with migration of data to a new database format. A method of upgrading a first version of an application installed on a first device to a second version is provided, where first and second transaction logs for respective first and second schema versions are stored in respective first and second log containers on a server computer, and the first version of the application stores data in accordance with a first schema version, and further stores a cache of at least a portion of the first transaction log in a log database on the first device, migrating the log database to the second schema version, storing a duplicate copy of the first transaction log in the second log container, and rewriting the duplicate copy of the first transaction logs using the second schema.

Schema versioning for cloud hosted databases

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for data storage. In one aspect, a method includes the actions of identifying a running query from an application; determining one or more data items of a plurality of data items that the application has permission to view according to one or more application specific access policies; and presenting the one or more data items to the application while not presenting other data items of the plurality of data items.

Cloud storage

Guarded file access operations are provided for creating and using guarded file descriptors, which can detect and prevent erroneous file access operations in computer programs. A file descriptor can be associated with a guard identifier to create a guarded file descriptor. The association can be established when the file is opened, and can be maintained independently of the computer program, which ordinarily maintains its own association between files, file descriptors, and guard identifiers. Subsequent file operations using the guarded file descriptor check that the guard identifier previously associated with that file descriptor is presented, and generate errors without performing the requested file operations if the correct guard identifier is not presented. This check serves as a validation of the computer program's use of file descriptors. An error and stack trace can be generated for use in analyzing a cause of the guard violation.

Guarded file descriptors

A method and apparatus for performing a function based on an executable code in response to receiving a request including function parameters are described. The executable code may be validated when loaded in a memory according to a signature statically signed over the executable code. A data location in the memory for storing the function parameters may be determined according location settings included inside the executable code. A target code location for storing a copy of the executable code may be determined based on the location parameters and the determined data location. A function is performed by executing the executable code from the target code location referencing the stored function parameters.

Dynamic trampoline and structured code generation in a signed code environment

Dynamic management of multiple persistent data stores is disclosed. One or more data objects are retrieved from two or more of a plurality of persistent data stores and provided to the client context in a manner such that the one or more data objects appear to the client context to come from a single source, even if in fact the objects have been retrieved from two or more different persistent stores.

Dynamic management of multiple persistent data stores

Dynamic management of multiple persistent data stores is disclosed. One or more data objects are associated with a client context, e.g., an instance of a client application program. The one or more data objects are retrieved from one or more of a plurality of persistent data stores and provided to the client context in a manner such that the one or more data objects appear to the client context to come from a single source, even if in fact the objects have been retrieved from two or more different persistent stores.

Managing cross-store relationships to data objects is disclosed. Specifically, cross-store relationships to data objects stored in a potentially dynamically changing set of persistent data stores is provided through a relationship definition that identifies a type of object to which the relationship pertains and specifies a property to be used to determine, which, if any, objects of the identified type are to be included in the relationship; by determining dynamically which, if any, currently available objects of the identified type have the specified property; and making available from among the objects of the identified type available at that time, if any, those objects, if any, that have the specified property.

Growing community of inventors

San Jose, CA, United States of America

Benjamin C Trumbull