changed "random" patch for higher precision

changed "random" patch for higher precision

[George P Nychis]

Hi,

I modified the "random" patch to support high precision averages ... the original random only supports 1-99% in integer intervals

The original patch did this by having an 8 bit integer, reading random bytes from the kernel into an 8 bit integer, and testing between 2 and 252 (1*2.55 and 99*2.55 ... 2.55 coming from 255/100).

Regardless of how the original patch worked, I use a 32 bit integer to support extremely high precision probabilities and changed the ranges to UINT_MAX instead of 255, plus other changes.

I tested it pretty rigurously on the 2.4 kernel because i'm working on a project right now which required high precision drop probabilities

My main question is, should i request changes to the random patch, or completely create a new patch and argument?

Thanks!
George

RE: changed "random" patch for higher precision

[Vincent]

Can you post the patch to the mail-list ?

Vincent

>-----Original Message-----
>From: netfilter-devel-bounces@lists.netfilter.org 
>[mailto:netfilter-devel-bounces@lists.netfilter.org] On Behalf 
>Of George P Nychis
>Sent: Sunday, April 30, 2006 12:01 PM
>To: netfilter-devel@lists.netfilter.org
>Subject: changed "random" patch for higher precision
>
>
>Hi,
>
>I modified the "random" patch to support high precision 
>averages ... the original random only supports 1-99% in 
>integer intervals
>
>The original patch did this by having an 8 bit integer, 
>reading random bytes from the kernel into an 8 bit integer, 
>and testing between 2 and 252 (1*2.55 and 99*2.55 ... 2.55 
>coming from 255/100).
>
>Regardless of how the original patch worked, I use a 32 bit 
>integer to support extremely high precision probabilities and 
>changed the ranges to UINT_MAX instead of 255, plus other changes.
>
>I tested it pretty rigurously on the 2.4 kernel because i'm 
>working on a project right now which required high precision 
>drop probabilities
>
>My main question is, should i request changes to the random 
>patch, or completely create a new patch and argument?
>
>Thanks!
>George
>

Re: changed "random" patch for higher precision

[Patrick McHardy]

George P Nychis wrote:
> Hi,
> 
> I modified the "random" patch to support high precision averages ... the original random only supports 1-99% in integer intervals
> 
> The original patch did this by having an 8 bit integer, reading random bytes from the kernel into an 8 bit integer, and testing between 2 and 252 (1*2.55 and 99*2.55 ... 2.55 coming from 255/100).
> 
> Regardless of how the original patch worked, I use a 32 bit integer to support extremely high precision probabilities and changed the ranges to UINT_MAX instead of 255, plus other changes.
> 
> I tested it pretty rigurously on the 2.4 kernel because i'm working on a project right now which required high precision drop probabilities
> 
> My main question is, should i request changes to the random patch, or completely create a new patch and argument?

I already have a version of random with higher precision queued
for 2.6.18. You say you're using UINT_MAX .. can you represent a
probability of both 0 and 1? :)

Re: changed 'random' patch for higher precision

[George P Nychis]

> George P Nychis wrote:
>> Hi,
>> 
>> I modified the "random" patch to support high precision averages ...
>> the original random only supports 1-99% in integer intervals
>> 
>> The original patch did this by having an 8 bit integer, reading random
>> bytes from the kernel into an 8 bit integer, and testing between 2 and
>> 252 (1*2.55 and 99*2.55 ... 2.55 coming from 255/100).
>> 
>> Regardless of how the original patch worked, I use a 32 bit integer to
>> support extremely high precision probabilities and changed the ranges
>> to UINT_MAX instead of 255, plus other changes.
>> 
>> I tested it pretty rigurously on the 2.4 kernel because i'm working on
>> a project right now which required high precision drop probabilities
>> 
>> My main question is, should i request changes to the random patch, or
>> completely create a new patch and argument?
> 
> I already have a version of random with higher precision queued for
> 2.6.18. You say you're using UINT_MAX .. can you represent a probability
> of both 0 and 1? :)
> 
> 
> 

Hey Patrick,

Well then this is perfect, because my implementation is for 2.4.32 ... i didn't touch the 2.6 stuff since my project is based on 2.4 kernel.

I can represent a probability of both 0 and 1, as soon as I finish up some work for the day, i'll send out my changes and patch and explain everything

- George