10.3 Free-Space Management

Need to protect:

  1. Pointer to free list

  2. Bit map

  3. Must be kept on disk

  4. Copy in memory and disk may differ.

  5. Cannot allow for block [i] to have a situation where bit [i] = 1 in memory and bit [i] = 0 on disk.

  6. Solution:

  7. Set bit [i] = 1 in disk.

  8. Allocate block [i]

  9. Set bit [i] = 1 in memory

Linked Free Space List on Disk