bogomips

[nathan r. hruby]

On Sun, 1 Dec 2002, Drew Lane wrote:

> How does clustering affect the bogomips value?
> 

It doesn't, BogoMIPS are a simple timing value to determine some timing of 
the processors local to the machine.  The BogoMips value (as it's name 
implies) is a bogus value, you would do well to aviod using it for 
anything other than geek bragging or comparasions between very similar 
machines.

Most clustering operates with a seperate library that assigns 
computational jobs to different nodes in the cluster.  The individual 
machines in the cluster are not really aware of the rest of the cluster.

This is different from say, an SGI Origian 3k where all of the compute, 
io, disk and power bricks operate as a single system image as the hardware 
has it's own internal fast switching fabric to make this happen seamlessly 
to the user.  Granted, you still need to write your apps in a parallel 
manner to take advantage this, but it's easier to maintatin.  Once your 
research is done, you can then split it Origina int o little bricks and 
take them to your office :)

> For example, will two clustered computers of equal
> processing power double the bogomips value?
> 

No.  That's why there are specialized tools for measuring cluster 
performance.  

> BTW, I noticed that the list of the fastest supercomputers
> has a Linux cluster in 5th place.
> 

Yes, many of the top 100 are Linux based clusters with more being built 
every day.

-n
-- 
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nathan hruby <nathan@drama.uga.edu>
computer services specialist
uga drama
http://www.drama.uga.edu/support/
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