[SR-Users] LCR "weight" column question

[Daniel-Constantin Mierla]

  Hello,

On 9/24/10 9:43 AM, Juha Heinanen wrote:
> [...]
> any ideas on how to improve weighted random number calculation without
> loosing performance?
>
maybe there are other options, but here is what I did for dispatcher 
weighted load balancing:
- each destination set has associated an array of 100 integers
- when destination set is loaded, this array is filled with indexes of 
destination addresses in the set as many times as associated weight value
- when this array is filled, the content is randomized

At runtime, a position of the last used index in array is keep, 
incremented and looped again over the array. During the load the 
100-indexes array is traversed 2 times, once to fill and second to 
radomize, but then selection is very fast at runtime, which is more 
important for a load balancer, since loading is done very rarely and in 
MI/RPC process, in parallel with normal operation using old data.

Code is in modules_k/dispacher/dispatch.c, function dp_init_weights().

Cheers,
Daniel

-- 
Daniel-Constantin Mierla
http://www.asipto.com