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- Understand the lecture slides and discussions thoroughly.
- Revisit the MPs and make sure you understand why you lost
any points and how to correct your mistakes. Seek help
from the TA of the instructor if you are unclear about
any aspects of these problems.
- Take the sample exams (midterm1, midterm2 and final
increment) as a dry-run for the actual exam.
The exam will cover all the lectures in the course. It is a
comprehansive exam. Listed here is the one topic, File Systems, not previously listed
in midterm1.syllabus.html or
midterm2.syllabus.html.
- File Systems
- File System Hardware Support
- Know how disks are organized
- Know how disk geometry influences how OS uses it to
implement a file system
- Use caches to reduce reads
- Organize data so that blocks read at nearly same time are
located in the sam cylander
- Know the four main ways to store files on the disk and their
pros and cons
- Contiguous layout
- Linked list
- Indexed Files
- Multi-level Indexed Files, including Non-uniform
Multi-level Indexed files
- Know what role the header (aka inode) plays and what
information needs to be in it for each layout
- Know how to read bytes from a file for each of the above
layouts, given access to the file's header
- File System Implementaion
- Know what a file system is
- an abstraction of stored data, more specifically, a
structured maping from symbolic user file names (typically in
ascii) to file header disk addresses
- Know how files are named in Unix, via paths
- Know what a directory is
- Know how a directory is stored in Unix
- Know how to use a directory structure to read bytes from a
file, given the file's path and the disk address of the header for
the root directory
- Know the basic steps to create, move, and delete a file
- What reliability issues exist when moving a file?
- What guarantees should the system strive for, even in the
case of system failures?
- Be able to reason about what deficiencies a particular order
of events will have when creating, moving, or deleting a file.
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