Enforce minimum delegation for a validator

[shaolin-flow]

Overview

Required for better control on who's allowed into the validator set

Suggested solution

Global variable can be set for increased DefaultPowerReduction which is used in staking module:

// PowerReduction - is the amount of staking tokens required for 1 unit of consensus-engine power.
// Currently, this returns a global variable that the app developer can tweak.
// TODO: we might turn this into an on-chain param:
// https://github.com/cosmos/cosmos-sdk/issues/8365
func (k Keeper) PowerReduction(ctx sdk.Context) math.Int {
	return sdk.DefaultPowerReduction
}

After off-line discussion with @yishay-dym @OrJah we're looking to increasing this amount for the froopyland testnet.

To-do

Set DefaultPowerReduction to 1000000000000 with the BondDenom as udym. This should be 1000000 million DYM.

Ref issues

• Turn staking Power Reduction into an on-chain param cosmos/cosmos-sdk#8365
• Changing PowerReduction param causing network halt cosmos/cosmos-sdk#9447

[mtsitrin]

It's set to 10^18

Not sure what u try to achieve here

[mtsitrin]

to change to 100K DYM