Difference between virtual and cache memory
Virtual memory vs Cache memory:
Computers play a huge role in the modern world. It has become vital in everyday life of the people in the modern world as equipment vitally used in their personal, academic, and business lives. There are a large number of areas that should be studied about computers. In the world of computers, memory is really important. It is what determines the fact whether a certain programme could be run or not. Memory is also kind of a limit upon which we base if a certain programme can be run or not. At present, memory is becoming almost ‘infinite’. However, computer memory types called ‘virtual’ and ‘cache’ are frequently mixed up by almost everyone except computer nerds. Since the differences between the virtual and cache memory are still unknown to almost a majority of people, this article endeavours to separately explain what virtual and cache memory are with a final paragraph describing their differences. As increasing the memory capacity would definitely be something you would like to know, it would be very constructive to get these two terms correct. To begin with, let us see what is meant by memory. Memory of computer is hardware that a computer uses to load the operating system and run programmes. It comprises of one or more RAM chips with each having several memory modules. The amount of real memory of a computer is confined to the amount of RAM installed in the computer. Most frequent memory sizes include 256 MB, 512 MB, and 1 GB.
What is virtual memory?
Since your computer’s equipped with a finite amount of RAM, it is possible that the computer run out of memory when too many programmes are running at the same time. This is the occasion where virtual memory comes in. what a virtual memory does is that it increases the available memory of your computer by enlarging the address space: places in memory where data can be stored. This process is done by using the space in the hard disk that is allocated for additional memory. The hard drive is generally much slower than the RAM and in that event data stored in the hard disk must be mapped back to the real memory in order to be used. That is to say, the data stored in the virtual memory in the hard disk cannot be used as they are there, but, they have to be mapped back to the real memory or the RAM so that they can be used. Further, this mapping process could take longer time and this means that the more virtual memory is used, the more it will slow down your computer. Hence, while virtual memory enables your computer run more programmes, it is better to have as much physical memory as possible so that the computer would mostly run programmes directly from the RAM.
What is cache memory?
Cache which is pronounced more like ‘cash’ and not ‘cashé’ is acknowledged as an extremely fast memory that is built into a computer’s Central Processing Unit (CPU) or located next to the CPU on a separate chip. The CPU uses the cache memory to stock up instructions that are repetitively requisite to run programmes, improving overall system speed. Further, the greatest advantage of cache memory is that the CPU does not have to use the motherboard’s system bus for data transfer. Whenever data are transferred all the way through the system bus, the transfer speed slows down the capability of the motherboard. As it happens, once most programs are open and running, they use very few resources. When these resources are kept in cache, programmes can operate faster and more efficiently. Moreover, cache is so effective in system performance that a computer running a fast CPU with little cache can have lower standards than a system running a somewhat slower CPU with more cache. Caches are placed inside computers basically via two methods: a cache that is built into the CPU itself is referred to as Level 1 (L1) cache and a cache that resides on a separate chip next to the CPU is called Level 2 (L2) cache. Although generally one type of cache is found in a CPU, some CPUs have both L1 and L2 caches built-in. Such caches are designated with the separate cache chip as Level 3 (L3) cache.
What is the difference between virtual and cache memory?
There are several differences between virtual and cache memories. The biggest difference would be that while the virtual memory is an amount of physical hard drive space used to store additional memory that the RAM is unable to store, cache is an area of RAM that contains areas of hard disk that have been requested by a component of the system at a later time. In addition, with virtual memory you can still use programmes or applications with larger memory. Yet, with cache memory, that cannot be done as it doesn’t enlarge or extend the amount of memory you have in your computer. What is does is, it just reduces the amount of time needed to access data. Moreover, using virtual memory would definitely slow down your computer, but when using cache memory, nothing like that happens. On the other hand, data that are put in the cache memory can be accessed faster and more efficiently. However, cache memory is very limited whereas virtual memory would suit your needs at the time with as much as temporary storage space.