Re: Optimizing a tapped delay (FIR) filter implementation

Kumar Appaiah wrote:


Jani Huhtanen wrote:

Same effect can be achieved by taking advantage of the mmu. Many OSs
allow you to map two pages to same physical address. In the sense of used
physical memory, this is free.

A quick search didn't yield much information. Could you just give me
some pointers on how to do this? Portability isn't much of an issue, so
I would like to learn about this.

BTW, I am on GNU/Linux.

Thanks.

Kumar

Search for 'ring buffer' and 'mmap':
http://www.google.com/search?q=ring+buffer+mmap&ie=UTF-8&oe=UTF-8

One promising result:
http://freshmeat.net/projects/vrb/

And I believe this can be done on any OS that supports some sort of shared
memory. That is, pretty much on every modern OS. I have myself implemented
such ring buffer for linux (or any posix compliant OS) as a C++ class.
However, the code is not in such a shape that I feel comfortable sharing
it. If you have problems with the implementation I can help with the
details.

--
Jani Huhtanen
Tampere University of Technology, Pori
.

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