Other
COS3721 Assignment 1 2023
- Course
- Institution
COS3721 Assignment 1 2023 Memo.
[Show more]
Seller
Follow
StudyWellNotes
Reviews received
Content preview
Assignment 1 - 2023 COS372119.03.2023
─
StudyWellNotes
, 1
Table of Contents
Question-1 Coverage : Chapter 1 3
Question 2: Operating-system structures 4
Question 3: Processes 5
Question 4: Threads and Concurrency 6
Question 5: CPU Scheduling 7
, 2
Question-1 Coverage : Chapter 1
1) Direct memory access is used for high-speed I/O devices in order to avoid increasing the
CPU’s execution load.
a. How does the CPU interface with the device to coordinate the transfer?(2)
b. How does the CPU know when the memory operations are complete?(2)
c. The CPU is allowed to execute other programs while the DMA controller is transferring
data. Does this process interfere with the execution of the user programs? If so, describe
what forms of interference are caused. (4)
a. The CPU can initiate a DMA operation by writing values
into special registers that can be independently accessed by the device. The device
initiates the corresponding operation once it receives a command from the CPU.
b. When the device is finished with its operation, it interrupts the CPU to indicate the
completion of the operation.
c. Both the device and the CPU can be accessing memory simultaneously. The memory
controller provides access to the memory bus in a fair manner to these two entities.
A CPU might therefore be unable to issue memory operations at peak speeds since
it has to compete with the device in order to obtain access to the memory bus.
2) Describe two challenges of designing operating systems for mobile devices compare with
designing operating systems for traditional PCs. (2)
The greatest challenges in designing mobile operating systems include:
● Less storage capacity means the operating system must manage memory
carefully.
● The operating system must also manage power consumption carefully.
● Less processing power plus fewer processors mean the operating system
must carefully apportion processors to applications.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller StudyWellNotes. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $11.71. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
80630 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now