

Scratchpad memory vs cache code#
In this method, data that is about to be accessed frequently is copied into the scratch pad using compiler-inserted code at fixed and infrequent points in the program. We propose a dynamic allocation methodology for global and stack data and program code that (i) accounts for changing program requirements at runtime, (ii) has no software-caching tags, (iii) requires no runtime checks, (iv) has extremely low overheads, and (v) yields 100p predictable memory access times.
Scratchpad memory vs cache full#
It is easy to see why a data allocation that never changes at runtime cannot achieve the full locality benefits of a cache. However, a drawback of such static allocation schemes is that they do not account for dynamic program behavior. A second category of algorithms partitions variables at compile-time into the two banks. Such methods incur large overheads in runtime, code size, energy consumption, and SRAM space for tags and deliver poor real-time guarantees just like hardware caches. Instructions are inserted before each load/store to check the software-maintained cache tags. First, software-caching schemes emulate the workings of a hardware cache in software. Primarily scratch pad allocation methods are of two types. It is motivated by its better real-time guarantees versus cache and by its significantly lower overheads in energy consumption, area, and overall runtime, even with a simple allocation scheme.

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