Summary: Appears in 34th Annual International Symposium on Microarchitecture, MICRO­34, Austin, Texas, December 2001 1
Direct Addressed Caches for Reduced Power Consumption
Emmett Witchel, Sam Larsen, C. Scott Ananian and Krste Asanovi’c
MIT Laboratory for Computer Science, Cambridge, MA 02139
witchel|slarsen|cananian|krste
#
@lcs.mit.edu
Abstract
A direct addressed cache is a hardware­software design
for an energy­efficient microprocessor data cache. Direct
addressing allows software to access cache data without a
hardware cache tag check. These tag­unchecked loads and
stores save the energy of a tag check when the compiler can
guarantee an access will be to the same line as an earlier
access. We have added support for tag­unchecked loads and
stores to C and Java compilers. For Mediabench C pro­
grams, the compiler eliminates 16--76% of data cache tag
accesses, with half of the benchmarks avoiding over 40%
of the data tag checks. For SPECjvm98 Java programs,
the compiler eliminates 18--63% of data cache tag checks.

Source: Ananian, C. Scott - One Laptop Per Child

Collections: Computer Technologies and Information Sciences