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Computer history TNO-FEL:
Control Data Systems

Using several relative CDC Cyber performance tables, a raw relative performance indication can be found in the table below. Note that no influence of the number of I/O channels, memory size and so on has been taken into account.

Relative performance CYBER systems
Performance  Relative CY810=1.0 
(computed)
 CY810= 1.0   CY840= 1.0   CY720= 1.0 
Cyber 995 76 69    
Cyber 990 42 38    
Cyber 960-32 33 30    
Cyber 176 24     15
Cyber 960-31 18 17    
Cyber 855 15     9.3
Cyber 760 15     9
Cyber 860 12 11    
Cyber 175 11     7
Cyber 960-11 11 10    
Cyber 750 11     6.7
Cyber 850 9 7   5.5
Cyber 932-32 7 6.7    
Cyber 845 6.5     4
Cyber 740 6.5     4
Cyber 840A 5.6 5.1 1 3.5
Cyber 730-1 4.2     2.6
Cyber 932-31 4.1 3.7    
Cyber 835 4.0     2.5
Cyber 74 4.0     2.5
Cyber 6600 3.9     2.4
Cyber 174 3.5     2.2
Cyber 930-31 2.9 2.6    
Cyber 730-1 2.6     1.6
Cyber 932-11 2.5 2.3    
Cyber 73-2 2.4     1.5
Cyber 173 2.2     1.35
Cyber 930-11 2.3 1.6   1.4
Cyber 830 2.0 1.4   1.25
Cyber 720 1.6     1
Cyber 172 1.6     1
Cyber 6400 1.6     1
Cyber 815 1.3     0.8
Cyber 73 1.5     0.9
Cyber 171 1.2     0.75
Cyber 72 1.1     0.7
Cyber 810 1 1   0.62

The DEC VAX 11/780 was rated as 1 MIPS by the Whetstone benchmark, a figure that equals a typical workload. DEC used this VAX 11/780 performance as its own relative performance base. Thus 1 VAX Unit of Performance (VUP) equals 1 MIPS.
DEC rated most multiple CPU systems as n* the VUP of a single processor, not taking into account the system overhead (sometimes over 20%). For that reason, competitors talked about a MIPS being a "Meaningless Indication of Processor Speed" or even about the "Marketing Indicator of Processor Speed".
For what it is worth, the CYBER 810 performance (the base of the left column above) equals 0.91 MIPS, the CYBER 932-11 rated 2&MIPS and the CYBER 990 (scalar) 25 MIPS.



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