Doi: 10.1145/1498765.1498785

The Roofline model offers insight on how
to improve the performance of software
and hardware.
BY SAmueL WiLLiAmS, AnDRe W WAteRmAn, AnD DAViD PAtteRSon
Roofline:
An insightful
Visual
Performance
model for
multicore
Architectures
conVentional WiSdom in
computer architecture

produced similar designs. Nearly every desktop and server computer uses caches, pipelining, superscalar instruction issue, and out-of-order execution. Although the instruction sets varied, the microprocessors were all from the same school of

 

design. The relatively recent switch to multicore means that microprocessors will become more diverse, since no conventional wisdom has yet emerged concerning their design. For example, some offer many simple processors vs. fewer complex processors, some depend on multithreading, and some even replace caches with explic-

itly addressed local stores. Manufacturers will likely offer multiple products with differing numbers of cores to cover multiple price-performance points, since Moore’s Law will permit the doubling of the number of cores per chip every two years. ⁴ While diversity may be understandable in this time of uncertainty, it exacerbates the

 

APriL 2009 | voL. 52 | no. 4 | communicAtionS of the Acm

65