Performance of the CPU Flashcards
Clock speed
the clock is the pulses that synchronise the components of the CPU
clock speed defines how many instructions are executed per second
when comparing similar CPU’s the higher the clock speed the faster the CPU can execute instructions
What is clock speed measured in?
Heartz
What is typical clock speed?
2-5 GHz
What happens when you increase clock speed?
also increase power consumption and heat generation
What did CPU manufacturers realise with clock speed?
consistently high clock speed can be an issue especially if limited by power or cooling
realised that clock speed can be manipulated to match the demand
Cores
one core is a fully functional processor in its own right
a multi-core effectively has many small processors on one die
What do multi-cores allow?
multiple instructions to be executed at once
How do you take advantage of having multiple cores?
programs must be written specifically
What happen when you all more cores?
increase performance
limits of cores
more cores draw more power
lower limit to how small you can make the features on a CPU(at a certain point electrons stop behaving and it becomes impossible to manufacture)
you can’t make CPU dies too big as electrons literally won’t have time too move around(among other issues)
often a compromise between clock speed and core count
Core tricks
performance cores are typically clocked higher and Eco (efficiency) cores are clocked much lower
CPU manufacturers are combining different types of CPU cores on a single CPU
What is cache?
small amount of data storage within the CPU (on the order of MB usually)
Cache
holds commonly used instructions and data to prevent constantly fetching from RAM
has much higher access speeds then RAM this speeds up execution of instructions significantly
