<p>You confused the definition of maximum throughput and throughput bound:</p>
<ul>
<li>Maximum throughput =  Capacity/Issue time</li>
<li>Throughput bound &quot;gives a minimum bound for the CPE based on the maximum rate at which the functional units can produce results&quot; (quoted from CSAPP). So throughput bound is the theoretical minimum CPE(Cycles per Element) caused by maximum throughput. Throughput bound = 1/maximum throughput.</li>
</ul>

CC BY-SA 4.0
2023-11-22T11:19:43.513Z
2023-11-22T11:28:15.327Z
2023-11-22T11:28:15.327Z
rigel
<p>In Chapter 5.7 of CSAPP, author list out the throughput boundary of Intel Core i7 Haswell while executing the operation Integer addition and multiplication, floating points addition and multiplication. Here is the function units list.<a href="https://i.sstatic.net/LCL4J.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/LCL4J.png" alt="enter image description here" /></a>
The author also pointed out the equation was throughput boundary = Capacity/Issue. Here is the data.<a href="https://i.sstatic.net/zzhja.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/zzhja.png" alt="enter image description here" /></a></p>
<p>I wonder how did the result equals to 0.5.<a href="https://i.sstatic.net/Pp8a7.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/Pp8a7.png" alt="enter image description here" /></a>
Because if the capacity is 2 and the issue is 1, it should be 2 right?</p>

CC BY-SA 4.0
2023-04-30T06:42:18.023Z
This question is not theoretical computer science, and it is off-topic on this site. Topic-wise, it seems it might belong to electrical engineering https://electronics.stackexchange.com/ , but I do not really know if this is a good question for that site.
Emil Jeřábek
CC BY-SA 4.0
2023-05-05T10:51:47.063Z
Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer.
Community
<optimization><ar.hardware-architecture>
How to calculate processor throughput boundary in CSAPP?
陳柔妍
# How to calculate processor throughput boundary in CSAPP?

(Asked by: username_0 on 2023-04-30)

In Chapter 5.7 of CSAPP, author list out the throughput boundary of Intel Core i7 Haswell while executing the operation Integer addition and multiplication, floating points addition and multiplication. Here is the function units list.[![enter image description here](https://i.sstatic.net/LCL4J.png)](https://i.sstatic.net/LCL4J.png)
The author also pointed out the equation was throughput boundary = Capacity/Issue. Here is the data.[![enter image description here](https://i.sstatic.net/zzhja.png)](https://i.sstatic.net/zzhja.png)

I wonder how did the result equals to 0.5.[![enter image description here](https://i.sstatic.net/Pp8a7.png)](https://i.sstatic.net/Pp8a7.png)
Because if the capacity is 2 and the issue is 1, it should be 2 right?

**Tags:** optimization, ar.hardware-architecture
> **Comments:**
> **username_1**: This question is not theoretical computer science, and it is off-topic on this site. Topic-wise, it seems it might belong to electrical engineering https://electronics.stackexchange.com/ , but I do not really know if this is a good question for that site.  
> **username_2**: Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer.  

---

## 1 answers

### Answer by username_3 on 2023-11-22. Score: 0

You confused the definition of maximum throughput and throughput bound:

* Maximum throughput = Capacity/Issue time
* Throughput bound "gives a minimum bound for the CPE based on the maximum rate at which the functional units can produce results" (quoted from CSAPP). So throughput bound is the theoretical minimum CPE(Cycles per Element) caused by maximum throughput. Throughput bound = 1/maximum throughput.


---

