Unit 2 Exam (Ian) Flashcards
What is binary?
A system of numerical notation in which each number is expressed as 0 or 1
Binary is made up of how many blocks
Binary is made up of blocks of 8bits of information and 8bits = 1byte of information
What is the highest number that you can make with 8bits?
is 255
Ascii
ASCII also uses binary for each letter and number
What is hex
Hex is a base 16 system used to simplify how binary is represented ( it goes from 1-9 then A,B,C,D,E,F)
What is a non-volatile memory and examples
Is memory that can be stored even if the computer is turned off e.g hdd, ssd, NVMe and flash drives
What is a volatile memory and example
Volatile memory is a memory that is not capable of storing any past data because it loses all the information if the computer turns off or is rebooted, e.g RAM
Why the hdd slows down when is full?
Because the hdd fills up the inner rings with data first and it can contain less data than the outer rings so when is full on the inner rings it moves to the outer rings which contain more data so that means when you read and write from them it will have more data per revolution so more transfer rate, making it slower.
What are the 3 types of Data transfer rate (DTR)?
IDE (PATA) - 133MB/s
SATA III - 600MB/s
M.2 NVme - 3.2GB/s
What is the lowest and highest spindle speed on a hdd?
The lowest commonly is 5400rpm
The highest is 15000rpm
What are the 3 features of cache on a hdd?
Reading ahead or behind
Speed matching
Write acceleration
What is cache?
is a memory that allows to speed up data transfers
What is defragmentation on a hdd?
is the process of reorganizing the data stored on the hard drive so that related pieces of data are put back together, all lined up in a continuous fashion and not all separated across the hdd
Why are SSD’s better than hdd?
SSD are faster than hdd because there is zero latency/seek time this is because the ssd doesn’t contain a spinning platters which take time to move to the correct position.
Does SSD suffer from fragmentation?
No, because the files can be split into lots of different memory addresses and still be accessed in sequence without any delay.
What is the limitation of an SSD?
The limitation of an ssd is that is costs more than a hdd.
Main benefits of an SSD
It has a faster DTR than any hdd on the market
Because it has no moving parts is harder to break from a drop impact
It allows the IOPS to be 10/50x faster than the hdd one.
Need less power to run an SSD
What is a NAS box?
Is a private cloud service in a office
Benefits of NAS
Benefits of NAS are that you can have more storage space than any other cloud without spending loads of money, another benefit is that is flawless collaboration so authorised users can access any files they have permission to through the NAS system/service, another benefit is that it has an automated data backup.
Main benefit of NAS vs External HDD
It has redundancy by raid because you can use more than 1 HDD to allow redundancy to be better and backup too. Where as in an external hdd if you drop it can break, can be stolen, it doesn’t have redundancy
What is RAID?
Raid is the way of combining several independent and relatively small disks into a single storage of a large size for the purpose of redundancy
How can you organize data in a RAID array?
You can organize data on a RAID array through different RAID levels that have different speed and fault tolerance properties
What is fault tolerance?
The ability to survive of one or more disk failures
What is RAID level 0?
RAID level 0 offers no redundancy but excellent performance by stripping data across at least two disks
so when the first disk is doing file 1,3,5 the second disk at the same time is doing the files 2,4,6 so it’s performance is super quick but has no redundancy. The data is divided into blocks then written to disks, raid level 0 should never be used for any critical data/system
RAID LEVEL 1 ( mirror)
In RAID level 1 mirroring stores two identical copies of data on two hard drives, so if one fails the other one has everything that the other had because it “mirrored” everything from the main one to the second one. it reads faster because you can read the data from both disks at the same time so you can read on the main disk the file 1 and at the same time the file 2 on the second disk because is all the same files as its mirrored
RAID LEVEL 5 (stripe with parity)
RAID5 writes data blocks evenly to all the disks, in a pattern similar to RAID0. However, one additional “parity” block is written in each row. and with that if one disk fails and the block of that disk is unreadable the contents of this block can be reconstructed using parity data together with all the remaining data blocks, only one disk can fail (3 disks minimum) you can use this for a database because it offers great performance and redundancy
RAID LEVEL 1+0
RAID LEVEL 1+0 is a RAID level where it uses the speed of RAID 0 and the redundancy of RAID 1, so its needed 4 disks for this RAID level and it works by the 2 RAID level 1 disks mirroring everything that comes from the 2 RAID level 0 disks, making it insanely quickly and super safe because if a disk fails you can have the other one that has been mirrored to rely on fault tolerance.
What are the CPU performance factors?
Clock Speed Design of the CPU Cache memory/size Number of cores Cooling system
What is Clock speed? and how is that a performance factor?
Clock speed is the number of processing cycles carried out every second and by cycles it means that it can execute billions instructions every second, and a larger clock speed produces better performance.
How does the design of the CPU affect its performance?
How tiny the circuits can be made and that allows more circuits on the chip, which runs slightly faster as the parts are closer together.
How does the cache of the CPU affect its performance?
Fast memory in the CPU that holds instructions waiting to be processed, a larger cache gives a better performance as more code and data can pre-loaded into the CPU.
How does the number of cores of the CPU affects its performance?
How many CPU core circuits are in the chip, it can be single, dual, quad, six or eight. A larger number of cores produces better performance.
How does the cooling system of the PC can affects CPU performance?
A CPU can get very hot, this is because of the design of the chip which has electricity flowing through it, this movement of electrons generates heat which if left unmanaged could damage the processor components, so you need a good cooling system so the CPU performance stays as it should.
What are some of the Cooling solutions?
Heatsink
Fan
Water cooling system
How does not taking care of your cooling system affect CPU speed?
If the CPU is allowed to overheat there is a temperature sensor onboard which will throttle back the clock speed of the CPU in an attempt to cool itself, doing this will reduce the performance of the chip.
How does a heatsink work?
Ambient air flow into the heatsink and expels hot air.
How does the design of the motherboard has a significant influence on the execution speed of the CPU?
Because the motherboard connects the CPU to the ram, graphics card and which devices. so if the motherboard design is different or doesn’t flow flow information between these devices then is advised to change motherboard as it can reduce execution speed
Amount and speed of RAM can also influence a lot on a computer speed
This is because if the system does not have enough memory it will have two options, close the program and lose data or use a page file, and a page file is a section of a secondary storage and if the system is forced to use a page file then the performance of the system will be dramatically decrease because the RAM is 70x faster than any secondary storage so if you’re not using RAM then it will decrease around 70x.
What are the methods of increasing execution speed?
Overclocking
CPU upgrade/motherboard
Why is a CPU upgrade/motherboard a good method of increasing execution speed?
Because by upgrading your CPU you will have a higher specification processing chip, so it can do more cycles per second.
What is backing storage?
Backing storage refers to any non-volatile data storage that will retain a computer’s data even after the computer is turned off.
What is backing storage used for?
Backing storage can be used to store files, store installed applications, store the OS and also to prevent your information from being lost.
What is the hard drive structure
Track
Sector
Sector of a track
Cluster
