Need help with algorithm

[MegaPowerRockstar]

Hi,
I need help with logic.

My requirement is, when someone calls my svc i need to pick a value from 2 values (A and Y) based on percentage basis.
A should be assigned 80%
Y should be assigned 20%

This is based on requests received to the service. Could you please help me how this can be achieved.
 

[MegaPowerRockstar]

ltt

[rmJU72]

On receiving a request, generate a random number between 1 and 10. If <=8 choose A else choose B

[Vaampire]

Just now, rmJU72 said:

On receiving a request, generate a random number between 1 and 10. If <=8 choose A else choose B

This should work.

other approach is tracking how many times a was picked and how many times b was picked.

[MegaPowerRockstar]

If we have multiple instances code is deployed, every instance will have its own random generation right.
 

[hunkyfunky2]

2 minutes ago, MegaPowerRockstar said:

If we have multiple instances code is deployed, every instance will have its own random generation right.
 

Do you want algorithm or practical solution with existing tool / environment? 

Above Algo is 100% right assuming it's done at load balancer / gateway level. 

 

 

 

[rmJU72]

It will average out to what you need.

If 100 instances and each instance gets 100 requests, each instance will choose 80 of A and 20 of B. Total across instances will be 8000 of A and 2000 of B.

[hunkyfunky2]

5 minutes ago, hunkyfunky2 said:

Do you want algorithm or practical solution with existing tool / environment? 

Above Algo is 100% right assuming it's done at load balancer / gateway level. 

 

 

 

If all instances get roughly same number (round robin ) then it will still work 

 

[MegaPowerRockstar]

ok thanks

[michaeledwards]

I had similar situation va, create a dictionary with group name and count, for each request randomly pick a number between 1-100 and then if its betweem 0-80 assign A else assign B, and for next iteration ignore the previously selected values while generating the random. 

 

once you hit the 100 values, clear the dictionary

[kathiramdasu]

What you are asking is how to implement canary deployment ?

Basic - go through cycle of requests coming in 1-8 goes to A and last 2 goes to B. Reset the counter.

Generate a random number between 0-1. if it is less than .8 send it to A more than .8 send to B. Here we cannot guarantee the distribution since any random generator in an language is not truly random, they are pseudo random.

[Spartan]

Anna ..first of all idi algorithm endi..

just a random number generator function

Loadbalancer meeda weighted distribution pedite...simplle assign 80-20 done..

ledu function rayali ante..

 

module.exports.hola = async (event) => {
  let random = Math.floor((Math.random() * 10) + 1);
  if(random > 8){
    statusCode: 200,
    //send traffic to A
	body: JSON.stringify(
      {
        message: 'sending traffic to A',
      },
      null,
      2
    ),
  }
  return {
    statusCode: 200,
	//send traffic to B
    body: JSON.stringify(
      {
        message: 'sending traffic to B',
      },
      null,
      2
    ),
  };
};

ps: @sri_india  anna..paina code lo emaina tappul unte.

kottaga nerchukuntunna

[Spartan]

implement chesava leda

[BeeerBob123]

On 12/9/2021 at 8:11 AM, MegaPowerRockstar said:

Hi,
I need help with logic.

My requirement is, when someone calls my svc i need to pick a value from 2 values (A and Y) based on percentage basis.
A should be assigned 80%
Y should be assigned 20%

This is based on requests received to the service. Could you please help me how this can be achieved.
 

ok

[rajnik]

If you are using Spring, try  spring cloud gateway

https://cloud.spring.io/spring-cloud-static/spring-cloud-gateway/2.0.2.RELEASE/single/spring-cloud-gateway.html

Its not going to be 100% exact but it works approximately for traffic routing. I had to implement custom traffic routing since my management wanted exact numbers. For ex: If it is configured 60/40 they wanted 60% traffic to goto one server and 40% to another exactly.