week 1 lecture Flashcards
what are the 4 fundamental tasks of a computer
Input
Process
Output
Store
what does CPU stand for
Central Processing Unit
what does the CPU do?
Performs the fetch-execute cycle
what is the fetch-execute cycle
o Fetch next program instruction from
memory
o Decode the instruction into actions
o Command the relevant part(s) of the
computer to operate to execute the
instruction
o Store the result somewhere (if necessary)
what does the CPU consist of?
Control Unit
Arithmetic Logic Unit
what does the CPU Control Unit do?
Handles the fetch-execute cycle
* Controls the other components of the computer through
signals
* Contains registers for important pieces of information like
the memory location of the next instruction
what does the CPU Arithmetic Logic Unit (ALU) do?
Digital circuits to perform arithmetic and logic
operations
* Data registers to store data being used by the current set
of instructions
What are the different CPU Registers?
o Data registers
o Program Counter
o Instruction Register
o Status Flags
o Stack Pointer
What are the types of memory?
from fast to slow:
o Registers (SRAM)
o Cache (on-chip and off-chip) (SRAM)
o Main memory (DRAM)
o Secondary storage (har
what does an operating system do?
Mediate access to CPU, Memory, I/O Devices
what is the core component of an operating system?
Kernel
Where is the kernel located?
Memory
what tasks does the OS handle
– Process management
– Memory management
– Input/output
– User interface
what are the main functions of Kernel
- Processes: Determines which processes are
allowed to use the CPU - Memory: Keep track of memory – what
memory is allocated to each process, what
memory is free - Device Drivers: Interface between hardware
(e.g disk and I/O) and processes - System Calls: Processes use system calls for communication with Kernel
how many web servers run on Linux?
nearly 2/3rds
