Instructions per second

The instructions per second ( IPS for short , from English instructions per second ), usually specified as millions of instructions per second ( MIPS , from English million instructions per second or mega instructions per second ), is a unit of measurement for the computing power of computers , in particular the performance of the CPU (see also computer benchmark ). The unit indicates how many machine instructions (instructions) a microprocessor can execute per second . 1 MIPS means it can execute a million machine instructions per second.

Processors achieve high IPS values ​​primarily with very simple commands for integer or logic calculations. For many calculations, however, the computing power with floating point numbers is decisive, for which there is a similar unit of measurement, " FLOPS " ( Floating Point Operations Per Second - floating point commands per second ).

Overview

Since machine languages ​​of processor types of different architecture (such as x86 and PowerPC ) often have very different instruction sets, a comparison of pure MIPS numbers is usually only of limited significance. If one takes similar functions as a reference, the differences are much larger than shown by the MIPS values. For example, the "integer multiplication of two registers" of an Intel 8080 or Zilog Z80 is an 8 bit × 8 bit = 16 bit operation, but with modern processors it is a 64 bit × 64 bit = 128 bit calculation that is carried out on an Intel 8080 Would take 10,000 bars.

For some areas of application, in which mainly integers, texts, data transport or administrative tasks arise, IPS information can mean a rough estimate of the performance of a system for these purposes; Examples are web, file and database servers, routers, device controls, smartphones.

Sample values

MIPS development timeline

CPU	MIPS	Clock frequency	year
Intel 8080	0.4	2 MHz	1974
Z80	0.625	2.5 MHz	1974
Motorola 68000	1	8 MHz	1979
Motorola 68020	4th	20 MHz	1984
ARM2	4th	8 MHz	1986
Motorola 68030	11	33 MHz	1987
ARM3	12	25 MHz	1989
Motorola 68040	44	40 MHz	1990
Intel 486DX	54	66 MHz	1992
DEC Alpha 21064 EV4	300	150 MHz	1992
Motorola 68060	88	66 MHz	1994
ARM 7500FE	35.9	40 MHz	1996
Atmel AVR	10	10 MHz	1996
PowerPC G3	671	366 MHz	1997
Zilog eZ80	80	50 MHz	1998
ARM10	400	300 MHz	1999
Pentium 3	1,354	500 MHz	1999
Athlon FX-57	8,400	2.8 GHz	2005
Athlon FX60	18,938	2.6 GHz	2006
Xeon Harpertown	93,608	3 GHz	2007
ARM Cortex-A15	35,000	2.5 GHz	2010
AMD Phenom II X6 1100T	78,440	3.3 GHz	2010
AMD FX-8150	108,890	3.6 GHz	2011
Intel Core i7 2600K	128,300	3.4 GHz	2011
Intel Core i7 5960X	336,000	3.5 GHz	2014

calculation

The performance , expressed in instructions per second, is given by ${\displaystyle \textstyle L}$

${\displaystyle L={\frac {1}{CPI\cdot T}}\quad IPS}$

where is the clock cycle length and the average number of cycles it takes for the computer to execute an instruction. ${\displaystyle \textstyle T}$ ${\displaystyle \textstyle CPI}$

Multiples of the unit of measure

As with other units of measurement, the multiples of an IPS are also described with the usual decimal prefixes (see also prefixes for units of measurement ) .

Today, however, the “MIPS” (for mega-IPS = 10 ⁶ IPS) is still common, as it virtually bridges the gap between the weakest and the strongest computing power in the consumer area. However, the multiples GIPS (for Giga-IPS = 10 ⁹ IPS) and TIPS (for Tera-IPS = 10 ¹² IPS) are also increasingly being used. The latter, however, is more likely to be the case with high-performance computers .

A measure for the performance of a microprocessor that is no longer used is the “KIPS” (for Kilo-IPS = 10 ³ IPS). The name KIPS is also used as a joke name for microprocessor designs developed by students during their training.

DMIPS

A MIPS value determined according to the Dhrystone benchmark.

Trivia

Due to the difficult comparability of IPS values above architecture boundaries is MIPS sporadically jokeful as " M isleading I nformation to P romote S ales" ( Misleading Information for sales promotion ) or as " M eaningless I ndication / I nformation about P rocessor S peed “( meaningless information / information on the speed of a microprocessor ).

See also

• BogoMips
• Instructions per cycle

Individual evidence

1. ↑ ftp://137.208.3.70/pub/lib/info/dec/alpha-infosheet.ps.Z  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.  
2. ↑ http://www.avrtv.com/2007/09/09/avrtv-special-005/