lecture 11 Flashcards
System concepts, Memory and Memory Hierarchy
non volatile memory –> loss of power =
no loss of data
volatile memory –> loss of power =
loss of data
volatile memory is
registers and cache (CPU)
main memory (real or physical)
what do all volatile memory types have?
read/write operations
CPU =
central processing unit
what body part is the CPU like?
brain of the computer
parts of the CPU
CU
ALU
registers
control unit
cache
i/o bus
clock
what does the i/o bus do?
allows read/write data onto the bus
CPU is able to exchange data with main memory, secondary storage, graphic card, etc bc of this
what does the controller permit for the RAM, SDD, graphic card, etc?
controller component allows them to communicate with the CPU and exchange data
does the CPU have a controller?
yes, allows the CPU to communicate (send/receive data) with other hardware components
what is the BUS?
the BUS facilitates exchange of data between all components in the computing system –> physical connections ONLY (copper wire)
word size of BUS (bit size)
of copper wires = bit size of BUS
how many components can read from the bus at the same time?
however many
how many components can write on the bus at the same time?
one only can write data on the bus
4 general types of memory used in computing system:
- registers
- cache
- main memory (RAM)
- secondary storage
what is at the top of the memory hierarchy
cpu registers –> smallest, fastest costliest storage device
what is at the bottom of the memory hierarchy?
remote secondary storage (cloud storage) –> largest, slowest, cheapest memory
what is at the middle of the memory hierarchy?
3 levels of the cache, main memory, local secondary storage (magnetic disks or solid state disks)
RAM =
random access memory
2 types of ram:
- SRAM –> static RAM
- registers and cache
- D Flip-flop tech - DRAM –> dynamic RAM
- transistor tech
- main memory
2 types of local secondary storage:
- magnetic disk storage (HDD)
- electro-magnetic disk –>
magnetic disk with tracks - solid state storage (SSD)
- flash memory (NOR and NAND,
non-volatile)
- not magnetic, no mechanical
parts that move or spin
- laptops, phones, etc
32-bit architecture –> how many bytes is 1 word?
4 bytes
64-bit architecture –> how many bytes is 1 word?
8 bytes
how many bytes can 1 physical address hold?
1 byte (8 bits)
main memory total amount =
of physical address locations * 1 byte
number of unique physical address locations =
2^# of physical address bytes
is word sized fixed?
yes it is fixed and determined by architecture
if the BUS is 32-bits, is everything else 32 bits?
yes bc it improves efficiency and system performance
