Components of OS Flashcards
operating system
is the whole package that manages
our computers resources and lets us interact with it.operating system,we’re talking about both the kernel and the user space
two main parts to an operating system
the kernel and the user space
kernel
kernel is the main core of an operating system. talks directly to our hardware and manages our systems resources.important function of the kernel is process management. Need to manage the order, how many reseources they take up, howlong they run, etc for programs. Switches the excution of the processes on CPU.
user space
The user space is basically made up of everything outside the kernel.The users thinks that we interact with directly
like system programs, user interfaces, etcetera
Kernel input/output or I/O management
Talks to external devices deviced like disks,keyboards,networks, co connections, audio devices and more. anything that can give us input or that we can use for output of data.
Kernal Process Management
A processs is a program thats executing, like out internet browser or text editor. A program is an application we can run, like chrome. We can have many processes running at the same time.
Programs
ram and the cpu are dedicated computer resources for programs. A Kernal has to manage our resources efficiently
time slice
is a very short interval of time that gets allocated to a process for CPU execution.CPU execute one process in milliseconds then executes another process then another.
Memory Mangement
when a process runs, it needs CPU time, but it also needs memory.Memory comes in smaller qtys. to five us more memory
Memory Mangement
when a process runs, it needs CPU time, but it also needs memory.Memory comes in smaller qtys. to five us more memory then we pysically have , we use virtual memory
Virtual memory
is a combination of hard drive space and RAM that acts like memory that out processes can yse. when we execcute a process we take the data of the program in chuncks we call pages.
Pages
if we cant to read and excute these pages, they ahve to be sent to the physical memory or RAM.
I/O Management
We refer to devices that perform input and output, as I/O devices. These include our monitors, keyboards, mice, hard disk drives, speakers, bluetooth headsets, webcams, and network adapters. the kernel needs to be able to load up drivers that are used, so that we can recognize and speak to these different types of hardware
I/O Kernal & Drivers
the kernel needs to be able to load up drivers that are used, so that we can recognize and speak to these different types of hardware. When the Kernel is able to start the drivers to communicate with hardware,it also manages to transfer of data in and out of the devices. Kernals doesnt just mean transdfer of data between us and the devicesm the devices also need to beable to talk to each other.
Shell (OS interaction)
There are also some shells that use graphical user interfaces. There are command line interface or CLIA shell. means using text commands. A shell is basically a program that interprets text commands and sends them to the OS to execute.most common shell, Bash or Bourne Again Shell in Linux.Windows called Powershell.
graphical user interface (GUI)(OS interaction)
visual way to interact with a computer.
Logs
Logs or files that record system events on our computer. Just like a systems diary our computer will record events like when it was turned on, when a driver was loaded and even when something isn’t working in the form of error messages.
Boot Process
When we start up a computer, we use the term boot.he boot process follows a general pattern. First computer is turned on. BIOS/UEFI runs a proces called the power on self test or POST.depending on the BIOS/UEFI configuration, a boot device will be selected ( Devices that are attached to our system, like hard drives, USB drives, CD drives, et cetera).the computer will search for what’s known as a bootloader from device. once found it executes this program.
BIOS/UEFI (Boot Process)
is a low-level software that initializes our computer’s hardware to make sure everything is good to go
POST (Boot Process)
performs a series of diagnostic tests to make sure that the computer is in proper working order
bootloader (Boot Process)
is a small program that loads the operating system
