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RE: DPD vs. BID hardware



 

John Crawford wrote on Fr 23.06.2006 16:50:

No, Michel, everyone does not agree that DPD is more hardware-friendly
than BID. 

We, as an independent Software vendor, came to 
the conclusion after one year investigation on 
the issue, that DPD Is more Intel and AMD HW 
friendly format than BID for the reasons I 
posted previously. 

- Nobu

I got a couple of off line comments on my statement.  
I therefore wish to answer the questions here.

The subject of our discussion is an industry 
standard. The standardization is successful, 
when the industry implement the standard broadly. 

There exist DPD implementations, which are available.  
We have verified the existing DPD implementations, 
and confirmed the value of DPD format, quality and 
performance of the existing implementation for broad 
applications.  

The situation for BID is, that there exists no 
implementation which is available. We have done the 
feasibility study for the BID claims, and we so far 
cannot verify the claims. There are many issues, but:

   1) lack of 128 bit register in Intel and AMD CPUs.
   2) nature of the binary encoding format
       - toilsome rounding at particular decimal 
         positions
       - inefficient extraction of particular decimal
         positions
       - etc

are the major reasons, why we assume that BID is not 
suitable for decimal applications.  

The absence of evidence should be in this case 
interpreted as an evidence of absence - that BID 
claims failed.

Now considering the above facts, DPD is ready to be 
standardized, while we first should request the 
proponent of BID to present some evidence in form 
of implementation before we can standardize BID.  

But I also agree to the position, that BID claims 
can be fulfilled some day, therefore BID can be 
standardized today as one of non data exchange 
formats.  

- Nobu

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