Questions tagged [computer-architecture]
Questions about the organization and design of computer hardware.
196
questions with no upvoted or accepted answers
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Is there any defined programming model for 'Self-Learning' NPUs?
Qualcomm is creating a Neuromorphic Processing Unit or an NPU called zeroth.
IBM is also working on a brain inspired chip under Synapse program.
Standford's Neurogrid might be a similar example.
...
4
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89
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Is there a OSI model equivalent for describing the abstract layers present in performing a computation for an operating system?
In describing where a system vulnerability exists, I often find a need for a model that partitions a operating system and its components into abstraction layers. Similar to how the Open Systems ...
3
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1
answer
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Load and Store Data hazard problem in 5-stages pipeline
Hi everyone and first of all thank you for been reading.
I'm a little confused about data hazard dependences when a "Store" instruction is followed by a "Load" instruction.
(Assume that we're working ...
3
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0
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230
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Is it possible to figure out cache size and associativity using the length of offset, index, tag fields?
I have a question where I am asked to find the size of a cache. I am given the following info:
a) the length of a memory address
b) the number of bits for offset, index, and tag fields.
I know I ...
2
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0
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39
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Von Neumann mixed with Havard in modern CPU?
Modern CPUs (for a very wider range of "modern") use separate data- and instruction-caches. So at the core they (probably) have separate busses for data and instructions. Does that make the &...
2
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1
answer
63
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Why does CLRS refer to the disk parts as pages rather than blocks?
I recently decided to review the B-tree chapter (chapter 18, p 486 in 3ed) in Introduction Algorithms, and found that they call pages what I always referred to as blocks or clusters:
In order to ...
2
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1
answer
313
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What do "JAMZ", "JAMN", and "JMPC" stand for in Mic-1?
I am wondering what do JAMZ, JAMN, and JMPC stand for in Tanenbaum's Mic-1 architecture. I ...
2
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59
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Confused with an Instruction Cycle question
Here's the question
The content of PC in the basic computer architecture (given below) is 3AF. The content of AC is 7EC3. The content of memory at address 3AF is A32E. The content of memory at ...
2
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27
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Detecting Data and Control Hazards for a mips 5 stage pipeline
I'm practicing data and control dependencies, but having trouble detecting them. For this example, I'm assuming this pipeline is fully bypassed (with forwarding). I think the only data dependency is ...
2
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0
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34
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Finding the timestamps of processes implementing Lamport's clocks
I have been asked this question, but don't know how to go about answering it.
Three process, which are implementing Lamport's clocks, are running and a lot of events are taking, place including some ...
2
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2
answers
256
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Really confused about latency with pipelining
I finished watching a video about pipelining https://www.youtube.com/watch?v=eVRdfl4zxfI
which I thought made sense.
Latency is the amount of time it takes to complete each instruction. Even with ...
2
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0
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63
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What is "orthogonality" in the context of Instruction Encoding?
What does it mean by "orthogonality" in the context of Instruction Encoding?
Why CISC Architecture is orthogonal while RISC is not?
2
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52
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Compiler optimization which does an SMT-like optimization in software?
Say I had two functions called one after the other:
...
2
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0
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29
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What is tag-only forced cache inclusion called?
Is there a commonly accepted term for caches that are guaranteed inclusive with respect to tags but not data?
Inclusion can be helpful to simplify cache coherence, for which use only tags need to be ...
2
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31
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Is there one or more Page Tables
I saw a question similar to this one, and it was answered but the answer was kind of vague and I'm looking for a little more detail than that. The question I'm referring to is this one.
The answer ...
2
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1
answer
922
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Number of MUX required for Cache Mapping
I have read that the number of multiplexers required is equal to the number of bits in the TAG field. Is it true? If yes then why?
I know that the size of each multiplexer has to be S to 1, where S ...
2
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1
answer
1k
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How to find percentage of CPU time consumed during DMA operation?
Q) Consider 1MBps hard-disk is interfaced to the processor in a cycle stealing mode of DMA whenever $64$ bytes of data is available in the buffer,then it is transferred to main memory (1 word = 64 ...
2
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101
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Where does the CPU scheduler sit in a layered OS design
In a layered approach to OS design, each layer can only access routines from the layers below itself.
For example, say I had two levels: memory management and the CPU scheduler
Where does the CPU ...
2
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0
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91
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Write-To-Read Relaxation in Cache Consistency
Write-to-Read Relaxation means that for a processor:
later reads can bypass earlier writes
But what does that mean?
What exactly is the difference between a read and a write for a Cache?
An ...
2
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0
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207
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CISC, RISC and anything else?
Is there a processor architecture that falls outside the CISC and RISC categories?
I'm vaguely familiar with RISC and CISC; my research thus far indicates that either a processor is RISC or CISC, ...
2
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0
answers
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How is the size of a register related to the size of primary memory?
I understand that registers are temporary storage compartments which (usually) hold 8 bits, or 1 byte, of information at a time. This information is sent from a register into the Central Processing ...
2
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0
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524
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Given a program which when executed spawns two concurrent processes : semaphore X : = 0 ; Is it possible for process P1 and P2 to starve?
Given below is a program which when executed spawns two concurrent processes:
...
2
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974
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Why ternary computers like Setun didn't catch on?
Why ternary computers like Setun didn't become popular despite being cheaper and more reliable than binary computers, and also having important computational advantages? We could have had cheaper ...
2
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2
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544
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How to design a simpler Version of CARDIAC (Cardboard Illustrative Aid to Computers)?
I'm trying to make a simpler version of CARDIAC for only performing addition. Now, I am encountering several problems in making something similar and looking for some ideas (I'm new to Computer ...
2
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Will this address result in a cache hit or miss for these cache mapping functions?
The Problem: A CPU produces the following sequence of read addresses in hex.
Suppose the cache is empty to begin with and assuming an LRU replacement, determine whether each address ...
2
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0
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409
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Future register file in computer architecture
Results from the execution units are written into the future file when they complete (may be out-of-order). Upon operand fetching, you fetch from the future file and not the architectural register ...
2
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251
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MIPS limited dual issue
Some of the MIPS processors like 5kc, 5kf have "limited dual issue". Searching online it seems that this means that the processor allows for a dual issue in only some selected cases, but it is not ...
2
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0
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208
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Is there a prefered name for the “effective access time” formula?
Any CS class about caches will at some point address this classical formula (or a variant of it)
Effective_access_time = hit_time + miss_penalty * miss_rate
My ...
2
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1
answer
142
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How does RAID-5 algorithm locate the right device?
Please consider the following diagram of a RAID-5 array (Ignore the gray background):
Now, given a logical address, how can one return the device number (0-3)?
For example, DeviceByLogicalSector(50) ...
1
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0
answers
11
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Why place of MA in MB then copy from MB to IR rather than going straight from MA to IR
During the fetch stage of the fetch-execute cycle, why are the contents of the cell whose address is in the MA (memory address register) placed in MB (memory buffer) then copied to IR (instruction ...
1
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0
answers
67
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How the data is transferred from main memory to hard disk?
I understand that data is transferred from the main memory to the CPU and vise versa using the data bus. But, I am unable to understand, how the data is being transferred from the main memory to the ...
1
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0
answers
31
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How can DRAM memory speeds be improved?
What are some ways with which we can improve the speed of dynamic RAMs?
1
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0
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29
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system architecture or software architecture
I was trying to get started with a small project but I quickly realized I had to do more research on the subject.
Suppose, when creating a site, in production, there's a certain structure how the ...
1
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0
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29
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Number of stall cycles when there is only EX/MEM pipeline registers or only MEM/WB pipeline register
I am working on a problem which is related to The processor. The problem is the problem 4.12 in the book whose title is "Computer Organization and Design". The problem has the assumption as ...
1
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0
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35
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Transactional memory
I would like to understand what role does Transactional memory plays in memory organization, I know that To allow for more efficient parallel programming with higher performance, processor implements ...
1
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0
answers
36
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How does virtual and physical memory affect cache structure?
Working with a question that states:
Consider a hypothetical machine in which physical address space is
of 512 words and virtual address space is of 2048 words. The page
size is 8 words. What is ...
1
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0
answers
49
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Can old hardware be practically useful for CS problems of modern day?
Thinking about specific settings on WorldBuilding.SE, it turns out I need help from people who are more in touch with CS and Clusters. For those who curious about how it started, backstory here, ...
1
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0
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16
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K-Map Reduction Grouping Question
I have a simple question regarding reduction using K-Maps.
My professor gave this example:
While I somewhat understand that we can only group quantities of base 2 numbers, why did my professor group ...
1
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0
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54
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Were boolean logic used in the analog computers?
I began a simple collection of the events behind todays computers. My knowledege in these fields is so limited, and I read:
"In the 1930s and working independently, American electronic engineer ...
1
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0
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171
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Difficulty in understanding the concept of operand forward in pipeling and when to use split phase
Given below is a question from $\text{GATE } 2015 \text{ CS}$ paper,
Consider the sequence of machine instruction given below:
\begin{array}{ll} \text{MUL} & \text{R5, R0, R1} \\ \text{DIV} &...
1
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0
answers
116
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Two Vs Dual Port RAM
Regarding the difference between Two Vs Dual Port RAM Here is what I understand:
The first can read and write at the same time but can't read twice or read twice at the same time while the second can ...
1
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0
answers
20
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Is there any research on allocating memory across multiple non-contiguous regions?
From my understanding, malloc and-the-like allocate contiguous blocks of memory. It then returns to you the start address of the memory block.
This (and other ...
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0
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77
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How can a CPU be busy during DMA access with burst mode transfer
During burst mode in a DMA access, the DMAC has control over the bus for the whole transfer session which includes DATA PREPARATION time as well as DATA transfer time, after the transfer is over, the ...
1
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0
answers
38
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How to cascade register correctly?
Currently I have this 4 bit CPU as shown in the schematic diagram below.
What I wish to achieve:
Add one more output register to make the CPU output a total of 8 bits
Show alphabet using the 8 bits ...
1
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0
answers
43
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How can I get 8 bits output from 4 bit CPU?
I am very new to Computer architecture. I am thinking to add one more output register to this 4 bit CPU as shown below. However, I am not sure should I connect the output register to the current CPU. ...
1
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Getting the flit size in a Tiled Chip Multicore Processor(TCMP) system with a mesh architecture
Consider a TCMP system with, say, a 4x4 mesh Network on Chip (NoC) where each tile has a superscalar processor. It is given that that the TCMP uses 64-bit words and the inter-router link bandwidth is ...
1
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0
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76
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How to predict the time complexity of matrix multiplication and inverse on a GPU?
Nvidia GPU can speed up the matrix manipulation greatly. I want to have a basic idea to predict the consumed time for matrix manipulation.
How can I analyze the time complexity of matrix ...
1
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0
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How fast can 10 integer multiplications be executed?
This is self study, but not homework. I am reviewing some slides I found online and have come across the following question.
Question:
If the latency of integer multiply is $3$ and the cycles/issue ...
1
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0
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Does Nand Flash Type Affect the Read Latency Based on Page Content?
In general, we have these types of NAND flash cells: SLC, MLC, TLC, and QLC. Since MLC flash cells can store 2 bits, the content of the cell can be 00, 01, 10, or 11 which are detected using different ...
1
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0
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Where is the register position in a CPU (real image illustration)?
I hear that register is in CPU, but the CPU iamge I generally see doesn't mark the position of register, can anyone provide a ...