RhoSet

Event Re-added v101 → v219, v233 → v265, v273 → v277, v290 → current #16

Emitted when rho parameter is changed.

Useful for: subnet ownersvalidatorsminersanalyticsdevelopers

The Big Picture

Rho is an emission distribution parameter that affects how rewards are spread across participants. Think of it as controlling the 'steepness' of the reward curve. Higher rho concentrates rewards toward top performers - the best miners get much more than average ones. Lower rho flattens the curve - rewards are more evenly distributed even to mid-tier performers. Subnet owners tune rho based on whether they want to incentivize excellence (high rho) or broader participation (low rho).

Why This Matters

Rho determines whether it's 'winner take all' or 'everyone gets something'. High rho means top miners capture most emissions while average miners earn little. Low rho means more equitable distribution. This affects your earning potential and strategy.

Example Scenario

Subnet 6 is very competitive with wide performance gaps. The owner increases rho to reward excellence. RhoSet fires with the higher value. Top 10% of miners now earn 60% of emissions instead of 40%. Mid-tier miners see their rewards drop significantly, incentivizing them to improve or leave.

Common Questions

What's the relationship between rho and inequality?: Higher rho = more inequality (top performers get much more). Lower rho = less inequality (rewards more evenly spread). The exact curve depends on implementation details.
Should I prefer high or low rho subnets?: If you're confident you can be top-tier, high rho subnets are lucrative. If you're starting out or mid-tier, low rho subnets provide steadier (if smaller) earnings while you improve.
How does rho interact with kappa?: Kappa affects consensus scoring, rho affects emission distribution. High kappa + high rho creates very competitive, winner-take-all dynamics. Low kappa + low rho creates inclusive, broad participation.

Use Cases

Tune emission distribution characteristics
Monitor emission parameter changes
Analyze how rho affects reward inequality
Model emission outcomes under different rho values

How to Use This Event

→ Monitor rho on subnets where you operate
→ Track rho changes to understand reward dynamics
→ Model your expected rewards under different rho settings

From Chain Metadata

Rho value is set.

Triggers

Preconditions

Caller has admin/sudo privileges
New rho is within valid range

Effects

Postconditions

Rho updated for subnet
Future emission calculations use new rho

Side Effects

Affects emission distribution formula
Changes the shape of reward curves

Event Data

#	Name	Type	Description
0	arg0	u16	Event field #0 (u16)
1	arg1	u16	Event field #1 (u16)

Code Examples

import { ApiPromise, WsProvider } from "@polkadot/api";
import { stringCamelCase } from "@polkadot/util";

const provider = new WsProvider("wss://entrypoint-finney.opentensor.ai:443");
const api = await ApiPromise.create({ provider });

// Subscribe to RhoSet events
api.query.system.events((events) => {
  events
    .filter(({ event }) =>
      event.section === stringCamelCase("SubtensorModule") &&
      event.method === "RhoSet"
    )
    .forEach(({ event }) => {
      console.log("RhoSet:", event.data.toHuman());
    });
});

Version History

Version:

v101 block 1 2 args

v233 block 4,920,350 2 args

v273 block 5,659,032 2 args

v290 block 5,947,548 2 args Current

Runtime Info

View Source

Pallet Index: 7
Event Index: 16
First Version: v101
Current Version: v393

Back to SubtensorModule Events