In this article, we will know the Memory Hierarchy in Computer Architecture with diagrams and examples.
Memory is a workspace for the computer. It is an area where the programs and data used by the computer reside. Computer systems always combine serval types of memory devices. Some of them may be in-built components and some others might have to be installed independently.
These different memory elements support the working of computer in their own ways. But the fundamental job of all the elements is storage of information. it is describe that an ideal Computer Memory should be
- Very Fast
- Small
- Consume Low Power
- Robust and non-volatile.
- Cheap.
However practically, this is impossible. The different types of Memory devices offer different benefits and drawbacks. A brief hierarchy of memory elements as follows.
What is Memory Hierarchy in Computer Architecture?
A brief hierarchy memory elements in computer architecture are follows-
At the top level of memory hierarchy are the CPU’s general purpose registers. The CPU uses these registers while processing the data. The registers are the smallest memory elements is the memory hierarchy. Registers are most expensive memory elements.
2. Level One Cache
This is the second level of the memory hierarchy. Level one cache is available on the CPU itself it is usually very small in size(4KB to 32KB). It is larger than the size of the register available in the CPU. Since this cache is fixed on the CPU it is not expandable. The cost is lesser than that of registers.
3. Level Two Cache
The Level 2 cache available on the CPU can be placed externally. When on the CPU it is not expandable. When the cache is external, it is expandable it is usually much larger than 1 Cache (256KB or 512 KB).
4. Main Memory
The main memory system falls right below the level 2 cache memory is the low cost and bulk memory available for general purpose. It is relatively fast, but still bulky, expensive, and volatile.
5. I/O Memory
Below the main memory lies the I/O memory which is used by the peripherals. Such memory access is often slower than the main memory. some example of I/O memory are the video card memory or the flash Memory.
6. Virtual Memory
A virtual memory system is sued in most modern computer today. Virtual memory is occupies a portion of the disk drive an uses it as main memory. It can transparently copy data between the main memory and the disk as require by application.
Disk storage is relatively much cheaper than semiconductor memory; hence it makes sense to use disk memory as main memory.
7. Disk Storage
These can store large quantities of data cheaply and in a small space. Furthermore, these can be used for parament/ semi parament storage as data is not lost when power is removed. However, the access time is slightly slower than virtual memory.
8. Network storage
Below Disk storage is the hierarchy lies the Network Storage. The programs at this level stores data on a remote system connected via a network. Network storage can be used to implement Virtual Memory, Disk Storage, and Distributed shared Memory.
Network storage can be created by using cheap and unused disk storage spread over a network of computers. Network storage is slower compared to local disk storage.
9. Magnetic Tape and Optical storage
These are both very cheap and can store huge quantities of data in a small space. Typically they use removable media, and so are ideal for permanent storage of data. However, access times are extremely long.
By combining different types of memory in a single system, the designer can get the best of all words and build a relatively low cost system with a high capacity and speed.
Now’s your following concepts has been clears-
- What is the Memory Hierarchy in Computer Architecture?
- Explain Memory hierarchy or Explain in Details Memory Hierarchy with examples.
- What is Memory Hierarchy explain with diagram?
- Memory hierarchy in computer architecture notes
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