Apple Inc.

Andrew D Myrick

Lionel Divyang Desai

Karen A Crippes

David Michael Chan

Joseph Sokol, Jr

James C McIlree

Jonathan R Reeves

Dmitriy B Solomonov

Jeffrey D Curless

Rasha Eqbal

Ian P Shaeffer

Pierre-Olivier J Martel

Jeffrey R Wilcox

Tristan F Schaap

Robert W Hill

Jeremy C Andrus

John L Kelley

Joseph R Auricchio

Techniques for memory management of a data processing system are described herein. According to one embodiment, a memory usage monitor executed by a processor of a data processing system monitors memory usages of groups of programs running within a memory of the data processing system. In response to determining that a first memory usage of a first group of the programs exceeds a first predetermined threshold, a user level reboot is performed in which one or more applications running within a user space of an operating system of the data processing system are terminated and relaunched. In response to determining that a second memory usage of a second group of the programs exceeds a second predetermined threshold, a system level reboot is performed in which one or more system components running within a kernel space of the operating system are terminated and relaunched.

Memory management of data processing systems

A method and apparatus of a device for resource management by using a hierarchy of resource management techniques with dynamic resource policies is described. The device terminates several misbehaving application programs when available memory on the device is running low. Each of those misbehaving application programs consumes more memory space than a memory consumption limit assigned to the application program. If available memory on the device is still low after terminating those misbehaving application programs, the device further sends memory pressure notifications to all application programs. If available memory on the device is still running low after sending the memory pressure notifications, the device further terminates background, idle, and suspended application programs. The device further terminates foreground application programs when available memory on the device is still low after terminating the background, idle, and suspended application programs.

Resource management with dynamic resource policies

Techniques are disclosed in which a secure circuit controls a gating circuit to enable or disable other circuity of a device (e.g., one or more input sensors). For example, the gating circuit may be a power gating circuit and the secure circuit may be configured to disable power to an input sensor in certain situations. As another example, the gating circuit may be a clock gating circuit and the secure circuit may be configured to disable the clock to an input sensor. As yet another example, the gating circuit may be configured to gate a control bus and the secure circuit may be configured to disable control signals to an input sensor. In some embodiments, hardware resources included in or controlled by the secure circuit are not accessible by other elements of the device, other than by sending requests to a predetermined set of memory locations (e.g., a secure mailbox).

Secure circuit control to disable circuitry

In one embodiment, when a secondary application on an electronic device is selected for deactivation, the memory associated with the application can be gathered, compacted and compressed into a memory freezer file. The memory freezer file can be stored in non-volatile memory with a reduced storage footprint compared to a memory stored in a conventional swap file. When the selected application is to be reactivated, the compressed memory in the memory freezer file can be quickly restored to process memory.

Partially deactivated application with termination protection

Techniques are disclosed in which a secure circuit controls a gating circuit to enable or disable other circuitry of a device (e.g., one or more input sensors). For example, the gating circuit may be a power gating circuit and the secure circuit may be configured to disable power to an input sensor in certain situations. As another example, the gating circuit may be a clock gating circuit and the secure circuit may be configured to disable the clock to an input sensor. As yet another example, the gating circuit may be configured to gate a control bus and the secure circuit may be configured to disable control signals to an input sensor. In some embodiments, hardware resources included in or controlled by the secure circuit are not accessible by other elements of the device, other than by sending requests to a predetermined set of memory locations (e.g., a secure mailbox).

Compressed freezer files

System and method for compaction of compressed and uncompressed virtual memory

One or more memory coalitions of software processes are created and used to decide whether to perform memory reduction operations on a data processing system. One method in one embodiment includes adding a newly launched second process to an existing memory coalition in response to determining that the second process should be part of a memory coalition that includes a first process. In response to determining that available system memory (e.g. DRAM) is low, the system determines which memory coalition of foreground applications uses the most amount of system memory and then performs one or more memory reduction operations on that memory coalition in order to make more system memory available to other processes.

Coalition based memory management

In one or more embodiments, methods and apparatus are provided for simulating device communications such as those of the Universal Serial Bus ('USB') or the like. The methods and apparatus involve receiving host requests that represent commands in a communication protocol and are associated with communication endpoints, distributing the host requests across the communication endpoints in the order that they are received, to their associated endpoints to generate a distribution of requests, generating a reordered plurality of host requests by selecting the host requests from the communication endpoints in an order based upon the order in which the requests are received and one or more simulation factors, receiving device requests from a simulated device in accordance with the communication protocol, merging the reordered host requests and the plurality of device requests to form a merged sequence of requests, and performing commands from the merged sequence of requests in the order.

Growing community of inventors

San Francisco, CA, United States of America

Andrew D Myrick