Heap management is an important component that affects program performance. Need to balance: – Speed & performance of allocation/deallocation Memory utilization (reduce wasted areas) Ease of usage by the programmer C Dynamic Memory Allocation Functions from stdlib.h • void *malloc(size_t size) – Allocates size bytes and returns a pointer to the block. • void *calloc(size_t nmemb, size_t size) – Allocates nmemb*size bytes, sets the memory to 0, returns a pointer to the block. • void free(void *ptr) function – Frees the block at address ptr (returned by malloc/calloc), returns it to the system for re-use by subsequent malloc calls. Source … Continue reading Dynamic Memory Allocation & Heap Management

What Is A Memory Management Unit? The memory management unit (MMU) is a hardware component that is part of the CPU. The task of the MMU is to abstract the physical memory addresses to one or more virtual address spaces. When the MMU is enabled, the CPU accesses memory via virtual addresses which will be translated by the MMU to physical addresses before sending them on the memory bus. Every CPU core has its own MMU. Why Memory Abstraction? Memory abstraction has three big advantages: In a multi-tasking environment, an OS can assign a dedicated virtual address space to every … Continue reading MMU (Memory Management Unit)

An interrupt is the automatic transfer of software execution in response to a hardware event that is asynchronous with the current software execution. This hardware event is called a trigger. The hardware event can either be a busy to ready transition in an external I/O device (like the UART input/output) or an internal event (like bus fault, memory fault, or a periodic timer). When the hardware needs service, signified by a busy to ready state transition, it will request an interrupt by setting its trigger flag. A thread is defined as the path of action of software as it executes. The execution of the interrupt … Continue reading Interrupt Processing in ARM

What is an RTOS? An Operating System (OS) is in charge of managing the resources of your computer. It will put tasks on the CPU and take tasks off the CPU, giving each task the illusion that it owns the entire processor. It will implement some kind of scheduling policy, which dictates when a task should be given time to run on the CPU and for how long. It will also manage the memory in the system and the various bits of hardware attached. A general OS, such as Windows or Linux, is normally designed for throughput and fairness, with … Continue reading Introduction to RTOS Part-1

About vim : vim, which stands for “Vi Improved“, is a Text Editor. It can be used for editing any kind of text and is especially suited for editing computer program. Description vim is a text editor that is upwards compatible with Vi. There are a lot of enhancements above Vi: multi-level undo, multiple windows and buffers, syntax highlighting,  command line editing, filename completion, a complete help system, visual selection, and others. Vim has a particular working method, there are two main modes: the command mode and the other modes. The command mode lets you select the working mode that you want to … Continue reading Linux vim Editor command

What is a Thread? A thread is a path of execution within a process. Also, a process can contain multiple threads. Why Multithreading? Thread is also known as a lightweight process. The idea is to achieve parallelism by dividing a process into multiple threads. For example, in a browser, multiple tabs can be different threads. MS word uses multiple threads, one thread to format the text, other thread to process inputs etc. Process vs Thread? The typical difference is that threads within the same process run in a shared memory space, while processes run in separate memory spaces. Threads are … Continue reading All About Thread’S