I spent three days of work about a year ago converting all of my code to switch from NSP to IPP because I was told by a coworker that the IPP is faster. When I completed my effort, I found out that it was about 20% slower. Experts poured over my code and could not determine where I made a mistake. Currently, my code supports NSP and IPP versions dynamically, but the switch is always set to NSP.

I would like to make some experiments, as I outlined, to see if I can improve the situation. So I ask you:

• would you rush to install the latest code, if the last time you tried the "latest" code, it ran slower?


• does the latest version come with upgraded documentation that would explain better how to use the features?

Personally, when I first used the NSP, I found the documentation to be excellent. I find the IPP documentation average, in lacking in many areas.

But I digress - do you have any advice or answers to my original questions?

Thanks in advance

Thanks and I understand your point.

The way I figure is that if I can run these experiments, they will work in the new version as well, and I can properly benchmark the performance increases.

We use a variety of Intel processors in our products. Previously, we used an 866 MHz Pentium III (where I could get about 1 GFLOP of performance with the NSP)

We now use a 2.53 GHz Pentium 4.

I have compared NSP and IPP on both processors.

Do you have any ideas how much faster fixed point filters (like the 32 bit coefficient, 16 bit data) would run compared to floating point on this processor? Also, how much faster the direct form might run?