Hardware is an abstraction that provides primarily two things- ANSWER 1. Read block
at index "k"
2. Write block at index "k"
3. Allocate and Deallocate
Contiguous allocation- ANSWER DEFINITION: The contents of a file are stored purely in
order on the drive
CONS: Suffers from external fragmentation, because it is a contiguous approach of
system memory
Linked List Allocation - ANSWER DEFINITION: Each block contains a pointer to the next.
Requires iteration through drive blocks-drive accesses-for random access
CONS: Problematic in large files; App has to iterate through each node.
Chained Table Allocation- ANSWER DEFINITION: Chain store the linked list as a table in
memory to minimize disk access. It is called a File Allocation Table FAT
Indexed Allocation - ANSWER DEFINITION: Indexed allocation stores locations of each
, block in an index block referenced by the file control block
CONS: A pure index system limits file size
Multi-level Indexed Allocation - ANSWER Use direct and indirect blocks to increase
maximum file size
Chained Indexed Allocation - ANSWER Direct blocks with an additional indirect pointer
What are Inodes? - ANSWER 1. Index Nodes
2. Store file block information, along with some block pointers - but are usually smaller
(128B or 256B
(T/F) Does a bigger block size have a better data rate? - ANSWER True
T/F A bigger the block size implies a good disk space utilization. - ANSWER False
What about if it has a worse disk space utilization? - ANSWER Internal Fragmentation
T/F A smaller block size therefore a better data rate - ANSWER False, lower data rate
T/F A smaller block size therefore good disk space utilization - ANSWER True
MS-DOS File System - ANSWER 1. Maximum partition size for different block sizes.
2. The blank boxes are the forbidden combinations.
How would you keep track of a free block? - ANSWER (a) Store free list on a linked list
(b) A bitmap
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 Easton. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $13.99. You're not tied to anything after your purchase.