Operating Systems 2017F Lecture 18: Difference between revisions

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What's in a filesystem <br>
What's in a filesystem <br>
* data blocks <br>
* data blocks <br>
* metadata blocks <br>
* metadata blocks, you need someway to find the blocks<br>
<br>
<br>
How do you organize metadata?<br>
How do you organize metadata?<br>

Revision as of 18:18, 16 November 2017

Additional Notes

Lec 18

  • More on filesystems
  • How can you recover a fs and how do you delete a file?


A filesystem is a:

  • Persistent data structure
  • Stored in fixed size blocks (at least 512 bytes in size)
  • Maps hierarchical filenames to file contents
  • Has metadata about files somehow


What's in a filesystem

  • data blocks
  • metadata blocks, you need someway to find the blocks


How do you organize metadata?

First identify basic characteristics of the filesystem

You need a "superblock" which is a "summary" block that tells you about everything else

Normally the superblock is the first block of the filesystem

In the superblock

  • Type of filesystem
  • Size of the filesystem
  • How the filesystem is organized
  • Where can I find the rest of the metadata