TLB and snoop energy-reduction using virtual caches in low-power chip-multiprocessors

ABSTRACT

In our quest to bring down the power consumption in low-power chip-multiprocessors, we have found that TLB and snoop accesses account for about 40% of the energy wasted by all L1 data-cache accesses. We have investigated the prospects of using virtual caches to bring down the number of TLB accesses. A key observa¿tion is that while the energy wasted in the TLBs are cut, the energy associated with snoop accesses becomes higher. We then contrib¿ute with two techniques to reduce the number of snoop accesses and their energy cost. Virtual caches together with the proposed techniques are shown to reduce the energy wasted in the L1 caches and the TLBs by about 30%.

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INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.5 COMPUTER SYSTEM IMPLEMENTATION
      C.5.3 Microcomputers
          Subjects: Microprocessors

General Terms:
Design, Performance

Keywords:
CMP, low-power, snoop, virtual caches