1.1 Structural Approaches
The structural techniques typically segment the word-lines or the
bit-lines. Sub banking (also known as column multiplexing) technique
divides the data arrays into sub banks. Only those sub banks
that contain the desired data are accessed. The bit-line segmentation
scheme partitions the bit-lines. When the memory
cells are sampled, only required bit-line segments are discharged.
TheMDM (multi-divided module) cache consists of small modules
with each of them operating as a stand-alone. Only the required
small module designated by the reference presented to the
cache is accessed. Albonesi proposed the re-sizable selective ways
cache. The cache set-associativity can be reset by the software.
An other type of structural method is to a add small piece of
cache to capture the most recently referenced data or to contain
prefetched data. Line buffer designs were proposed to cache
the recently accessed cache lines. Filter cache is a small cache
that sits between the CPU and the L1 caches. It reduces L1 cache
power consumption by filtering out the references to the L1 caches.
Many of the structural approaches have been proved efficient. They
can be used with other strategies describe in the following sections.