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Administration space

Root ObjectContainer
Administration space

Administration space is space which is reserved for storing blocks which keep track of where files are located and what files are in what directories.  Only the Bitmap, the Root blocks and the information stored in the files themselves are not stored in administration spaces.

Administration space is allocated dynamically in chunks of 32 blocks at a time.   If all administration spaces are fully occupied then the filesystem will look for a new area on the disk and reserve it for storing administration blocks.  This means that administration spaces are marked in use in the normal Bitmap.   Administration spaces are managed seperately and each of the spaces has their own little bitmap.

The location of the admininstration spaces and their bitmaps are stored in AdminSpaceContainers.  Several spaces can be stored in a single AdminSpaceContainer.  AdminSpaceContainers are in a double linked list.   When looking for room to store an administration block this list is scanned to look for a free block in one of the administration spaces.  If such a block is found, then it is marked in use in the little bitmap belonging to the administration space.

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For comments, problems or questions regarding this page contact John Hendrikx.
Last updated: 17 oktober 1998.