Cache Memory Mapping Techniques Pdf

Android Memory Analysis Texas Instruments Wiki. Content is no longer maintained and is being kept for reference only Introduction. Content is no longer maintained and is being kept for reference only Android migration to non mobile segments. Following flavors of android has lead this OS migration to non mobile segments. Attractive licensing for investors and corporate. Open source. Strong eco system. Paging Faster Translations TLBs Using paging as the core mechanism to support virtual memory can lead tohighperformanceoverheads. Supports for embedded cc components. Development and debugging tools. Challenges for non phone segment. Balancing cost to performance ratio. Reduction in bills of material is necessary to make an impact on cost. Mainly this cost directly proportional to memory size and power efficiency. Use of DSP and SGX like components will give a gain on performance side. View and Download SpectraLink 8440 administration manual online. Wireless Telephone. IP Phone pdf manual download. Boot time It is very important to reduce boot time for segments like car infotainment,medical personal assistant,car navigation devices etc. Native application needs to be run along with android apps. Every non phone segment has customized application for a segment use case. Car navigation system has native map application should be running through out along with other android apps. Among all the challenges mentioned above, Current wiki will focus on cutting down cost on memory through footprint analysis and simple techniques to customize android OS. Wiki will cover. Boot time memory requirements e. MMC,MMCSD card, NAND etc. Run time memory requirements DRAM,DDR3 etc. Android customization for boot time and run time memory Note All examples or test mentioned in this document is tested on prebuilt binaries of AM3. Statistical Techniques Statistical Mechanics. However analysis and customization techniques can be applied to similar architecture Boot Time Memory. Boot time memory is non volatile memory which holds good amount of datalike boot loader, kernel images, file system etc required to boot android system. There are various boot options for android system. It can boot from on chip NAND or e. MMC or SD Card or serial flash or any other memory available on device. Following are the components which are part of this memory. Boot Loader. Kernel. File System Before Boot After BootMediaData Files if availableAbove diagram explains memory footprint of TI Android Gingerbread 2. Dev. Kit 2. 1 release for AM3. If youre away from home and in need of WiFi, now Facebook can help you find it. Originally only available in a few countries, the social networks Find WiFi. Reading Images IM by default will attempt to determine the image format type by the magic file identification codes within the file itself. If this fails however. A CPU cache is a hardware cache used by the central processing unit CPU of a computer to reduce the average cost time or energy to access data from the main memory. Mapping Terminology Mapping v. The act of determining how objects and their relationships are persisted in permanent data storage, in this case relational. Product Folder Sample Buy Technical Documents Tools Software Support Community An IMPORTANT NOTICE at the end of this data sheet addresses availability. Android At Runtime. Below table briefs about runtime memory utilization by different android processes applications Note Represent data are taken from RSS. Android system will. Create cache history for core framework and applications. Create database files to be used by applications. With respect to above statistics one required minimum of 1. MB non volatile memory to boot the android system. How one can bring down this figure Run Time Memory. This is the memory which is required run time for the execution of application or process or service. Typically RAM plays this role. Run time memory requirement solely depends on application use case that is required to execute on android OS. A lot of memory in android is actually shared across multiple processes. So how much memory a process uses is really not clear. Android Run Time Environment. There are mainly three possible run time environment with respect to android layers. Android app Runtime Service Lib. Android App   Java Application. Runtime Service Java Service. Lib Shared Object. Android app Runtime Service Native Service Lib. Android App Java Application. Runtime Service Java Service. Native Service CC Executable. AcghHZMwYFBkHpvNSDA.png' alt='Cache Memory Mapping Techniques Pdf' title='Cache Memory Mapping Techniques Pdf' />Lib Shared Object. Android app Runtime Service Native Daemon Lib. Android App Java Application. Runtime Service Java Service. Native Daemon CC Daemon. Lib Shared Object. For each java application service, the instance of DVM Dalvik Virtual Machine will be loaded into the memory. Runtime Service Native Service will communicate using IPC binder Android Implementation. Therefore binder library will be loaded into the memory. Runtime Service Native Daemon will communicate using sockets Kernel Implementation. In brief android run time environment mainly categorize into. Libraries Shared Objects. Applications. apk. Frameworks Core libraries Services. Services Run time android services. Daemon Run time Linux Daemons. Utilities Android Shell, systembin, systemxbin. Sew Eurodrive Cad Files. Memory Anatomy. PSS  Proportional Set Size. Amount of memory shared with other processes, account in a way that the amount is divided evenly between the processes that share it. This is memory that would not be released if the process was terminated, but is indicative of the amount that this process is contribution to overall memory load. USS  Unique Set Size. USS is the set of pages that are unique to a process. This is the amount of memory that would be freed if the application gets terminated. Heap. Runtime memory available for allocation Used by applications, services, daemons. Dalvik Heap. The dalvik heap is preloaded with classes and data by zygote. When zygote forks to start an application, the new application gets a copy on write mapping of this heap. As Dan Borstein says below, this helps with memory reduction as well as application startup time. Dalvik, like virtual machines for many other languages, does garbage collection on the heap. There appears to be separate thread called Heap. Worker in each VM process that performs the garbage collection actions. Dan Borstein note on heap sharing http www. Its used in Android to amortize the RAM footprint of the large amount of effectively read only data technically writable but rarely actually written associated with common library classes across all active VM processes. The heap created by the preloading process gets shared copy on write with each spawned VM process but again doesnt in practice get written much. This saves hundreds of k. B of dirty unpageable RAM per process and also helps speed up process startup. Commands for run time memory usage. To spit out a bunch of information about the memory use of each JAVA process. To see memory for particular process e. System. adb shell dumpsys meminfo system. Summary of the overall memory. Run Time Memory Gallery Use Case. Rum time memory usage will depends on kind of use case running on android system. Following are the context where run time memory will be allocated by android system. All java process will run with the instance of DVM. DVM will again have its own run time heap requirement based on java application code complexity. Binder IPC will allocate run time memory for marshalling objects. Service or daemon will allocated run time memory for internal usage. Following example will show run time heap change with respect to gallery application use case. Size Total size of particular heap. Allocated Portion of heap is allocated to process. Native Usage Usage by application or service code Dalvik Usage Usage by Dalvik virtual machine libdvmcom. After android bootcom. After opening gallery application. Note that, there is no big change in Dalvik heap but native code heap usage increased by 2 MB. Further complexity of use case application code will increase Dalvik heap as well. Android Framework  Memory Foot. Print. Below table brief about minimum memory requirments for the different core components of android os. Average 6. 5 8. 0 MB of minimum memory required for android to boot with sgx support. After boot android will launch many services and applications, which will add more memory to listed figure. Application Services will start creating instances of dalvik VM many other objects Table 1  android memory framework. Download V.B 6.0 Sample Of Games Software. Approx size in MB.