Editing Processor design (section)

===Performance analysis and benchmarking===
{{Main| Computer performance}}
[[benchmark (computing)|Benchmarking]] is a way of testing CPU speed. Examples include SPECint and [[SPECfp]], developed by [[Standard Performance Evaluation Corporation]], and ConsumerMark developed by the Embedded Microprocessor Benchmark Consortium [[EEMBC]].

Some of the commonly used metrics include:
* [[Instructions per second]] - Most consumers pick a computer architecture (normally [[Intel]] [[IA32]] architecture) to be able to run a large base of pre-existing pre-compiled software.  Being relatively uninformed on computer benchmarks,  some of them pick a particular CPU based on operating frequency (see [[Megahertz Myth]]).
* [[FLOPS]] - The number of floating point operations per second is often important in selecting computers for scientific computations.
* [[Performance per watt]] - System designers building [[parallel computing|parallel computers]], such as [[Google search technology#Current hardware|Google]], pick CPUs based on their speed per watt of power, because the cost of powering the CPU outweighs the cost of the CPU itself.<ref>{{cite web|url=http://www.eembc.org/benchmark/consumer.asp?HTYPE=SIM|title=EEMBC ConsumerMark|archive-url=https://web.archive.org/web/20050327005323/http://www.eembc.org/benchmark/consumer.asp?HTYPE=SIM |archive-date=March 27, 2005}}</ref><ref>{{cite web|url=https://www.zdnet.com/article/power-could-cost-more-than-servers-google-warns/|title=Power could cost more than servers, Google warns|author=Stephen Shankland|website=[[ZDNet]]|date=December 9, 2005}}</ref>
* Some system designers building parallel computers pick CPUs based on the speed per dollar.
* System designers building [[real-time computing]] systems want to guarantee worst-case response. That is easier to do when the CPU has low [[interrupt latency]] and when it has deterministic response. ([[Digital signal processor|DSP]])
* Computer programmers who program directly in assembly language want a CPU to support a full featured [[instruction set]].
* Low power - For systems with limited power sources (e.g. solar, batteries, human power).
* Small size or low weight - for portable embedded systems, systems for spacecraft.
* Environmental impact - Minimizing environmental impact of computers during manufacturing and recycling as well during use.  Reducing waste, reducing hazardous materials.  (see [[Green computing]]).  <!-- ... Are there other measures of "goodness", "figures of merit", that I'm missing here? -->

There may be tradeoffs in optimizing some of these metrics.  In particular, many design techniques that make a CPU run faster make the "performance per watt", "performance per dollar", and "deterministic response" much worse, and vice versa.