One Minute Evaluations for 25-27 November

CS 438 - Operating Systems Concepts

• Topic: File systems and files; file abstractions.

  Question: How much of a performance gain does one get from using a journaling filesystem such as ext3 or ReiserFS over a non-journaling one?

  One minute response: Roughly, journaling provides two main performance gains: file-system recovery is quicker with journaling because the meta-data scan is over the journal, which is small and localized, rather than over the disk-resident meta-data, which is big and spread throughout the partition. Second, journaling meta-data is I-O friendly, essentially being a single, big write-only data stream sloshing from the file namager to the disk. Make sure you visit the Namesys Web site, it's a hoot.

• Topic: Metadata and file abstraction.

• Topic: File systems.

• Topic: File systems and methods.

• Topic: We learned about file systems (low level).

  Question: Will you be posting the answers to the "white" test 3 on your website?

  One minute response: Oops. It's been fixed. Sorry.

• Topic: File blocks, sequential, clusters, read and write.

  Question: Who wins in a fight: Godzilla or Mothera?

• Topic: Talked about file management.

  Question: Happy Thanksgiving!

  One minute response: Thanks; same to you.

• Topic: File management.

  Question: What is metadata?

  One minute response: It's data about data.

• Topic: We studied file abstractions; disk files and their structures.

  Question: Why?

• Topic: File management; file management issues.

  Question: What's the difference between FAT 32/16, NTFS and The Unix one?

  One minute response: FAT is just that, a file allocation table. The 12-16-32 refer to the size in bits of the table indices. NTFS and the various Unix file systems provide more flexible file managment than does FAT, and is are better fits for large disk that is FAT. A review of Sections 11.2 and 11.3 of the text should help fill in the details.

This page last modified on 16 July 2003.