[sr-dev] avoiding hash calculation in xavp api function calls

[Daniel-Constantin Mierla]

Hello,

there are collisions on hash id, you can't rely on it as unique id.

I wanted to comment, but comment but didn't get to it yesterday, caught 
by other tasks.

Have you measured the impact? The same is done for avp with string names 
and there were no complains. All the operations are in memory and for 
such names which are quite short, there are not so many extra operations.

The option would be to store the id along with the string in pv name 
structure, but then it increases the memory, not only for xavps, but for 
all pv specs. SER guys dropped usage of avps with integer id because the 
overhead for using just string names was insignificant, compared with 
the complexity of dealing with both.

Probably optimizations can be done in lot of places, but at expense of 
something else, like more memory or more complexity (translated in 
harder code management).

Cheers,
Daniel



On 12/14/12 6:41 AM, Juha Heinanen wrote:
> i didn't get any comments about needless script time calculation of xavp
> name hash values.
>
> one hack to avoid the hash calculation could be such that if str *name
> passed to xavp api functions has len=0 then s contains pre-calculated
> hash value.
>
> -- juha
>
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-- 
Daniel-Constantin Mierla - http://www.asipto.com
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