Texas Instruments Titanium TI-89, User Manual

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Memory and Variable Management 694
Why Is Garbage Collection Necessary?
The user data archive is divided into sectors. When you first begin archiving, variables
are stored consecutively in sector 1. This continues to the end of the sector. If there is
not enough space left in the sector, the next variable is stored at the beginning of the
next sector. Typically, this leaves an empty block at the end of the previous sector.
Each variable that you archive is stored in the first empty block large enough to hold it.
Note:
An archived variable is stored in a continuous block within a single sector; it cannot
cross a sector boundary.
This process continues to the end of the last sector. Depending on the size of individual
variables, the empty blocks may account for a significant amount of space.
Note:
Garbage collection occurs when the variable you are archiving is larger than any
empty block.
variable B
variable C
variable A
variable D
Depending on its
size, variable D is
stored in one of
these locations.
Sector 1
Sector 3
Sector 2
Empty
block