David Atienza Alonso

Dynamic Memory Management Optimization for Multimedia Applications

As already introduced in the first two chapters of this book, due to increasing complexity and drastic rise in memory requirements, new system-level memory management methodologies for multimedia applications need to be developed.

Dynamic Memory Management for Embedded Systems

This book provides a systematic and unified methodology, including basic principles and reusable processes, for dynamic memory management (DMM) in embedded systems. The authors describe in detail how to design and optimize the use of dynamic memory in modern, multimedia and network applications, targeting the latest generation of portable embedded systems, such as smartphones. Coverage includes a variety of design and optimization topics in electronic design automation of DMM, from high-level software optimization to microarchitecture-level hardware support. The authors describe the design of multi-layer dynamic data structures for the final memory hierarchy layers of the target portable embedded systems and how to create a low-fragmentation, cost-efficient, dynamic memory management subsystem out of configurable components for the particular memory allocation and de-allocation patterns for each type of application. The design methodology described in this book is based on propagating constraints among design decisions from multiple abstraction levels (both hardware and software) and customizing DMM according to application-specific data access and storage behaviors.

Intermediate Variable Removal from Dynamic Applications

Modern software applications for embedded systems have massive data storage and transfer needs. This is particularly true for applications that need to deliver a rich multimedia experience to the final user.

Systematic Placement of Dynamic Objects Across Heterogeneous Memory Hierarchies

In the previous chapters we have explained how to improve different aspects of the memory subsystem when dynamic memory is used in an embedded system. In particular, we explained how to design efficient custom dynamic memory managers to serve the dynamic memory requests of the applications.

Dynamic Data Types Optimization in Multimedia and Communication Applications

In future technologies of nomadic embedded systems an increasing amount of applications (e.g., 3D games, video-players) coming from the general-purpose domain need to be mapped onto an extremely compact device. Furthermore, the general trend of ubiquitous mobile access pushes developers to provide cross-platform applications with the same characteristics across a set of devices and desktop systems. Smartphones, tablets, in-car entertainment and navigation systems offer access to the same applications that traditionally run on PCs and servers. However, these new embedded systems, struggle to execute these complex applications because they come from desktop systems, holding very different restrictions regarding memory use features, and more concretely not concerned with an efficient use of the dynamic memory.

Profiling and Analysis of Dynamic Applications

As explained in Chap. 2, the problem of optimizing the design of dynamic embedded systems lays on exploiting as much as possible static (design-time) knowledge on the applications, but still leaving space for run-time considerations that allow tackling dynamic variations without resorting to worst case solutions. This requires extensive information about the static and dynamic characteristics of the applications. However, there is not a standard definition or representation of software metadata to typify the characteristics of the dynamic data access behavior of applications because of varying inputs.

Analysis and Characterization of Dynamic Multimedia Applications

As discussed in Chap. 1, in nomadic embedded systems an increasing amount of applications (e.g., 3D games, video-players) coming from the general-purpose domain need to be mapped onto a cheap and compact device. However, embedded systems struggle to execute these complex applications because they come from desktop systems, holding very different restrictions regarding memory use features, and more concretely not concerned with the efficient use of the dynamic memory. Today, a desktop computer typically includes at least 2–8 GB of RAM memory, as opposed to the 256–1024 MB range present in low-power respectively high-end nomadic embedded systems. Therefore, one of the main steps during the porting process of multimedia applications (that were initially developed on a PC) onto embedded multimedia systems, involves the optimization of the dynamic memory subsystem.