Current Value
1.00 TAO (1000000000 raw)
Conversion: ÷ 10^9 (RAO → TAO)
Relevant for: subnet ownersdevelopersdevelopers
The Big Picture
Subnet owners can set MinBurn to control registration economics, but this constant caps how high MinBurn can be set. It prevents subnet owners from setting absurdly high minimums that would effectively close registration. It's a developers guardrail on subnet configuration.
Why This Matters
If you're configuring subnet parameters, know you can't set MinBurn above this ceiling. It protects would-be participants from exclusionary minimum costs.
Example
With MinBurnUpperBound of 10 TAO, a subnet owner cannot set MinBurn to 100 TAO. The maximum floor they can impose is 10 TAO, keeping registration accessible even on premium subnets.
Common Questions
- Why limit subnet owner discretion?
- Prevents abuse. A subnet owner could otherwise set MinBurn = 1000 TAO to exclude small participants. The bound ensures some accessibility.
- Can developers change this bound?
- Yes, via runtime upgrades. But changes affect all subnets and require careful consideration of accessibility impacts.
From Chain Metadata
Min burn upper bound.
Use Cases
- Burn limits
- Parameter validation
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 });
// Query MinBurnUpperBound constant
const value = api.consts[stringCamelCase("SubtensorModule")][stringCamelCase("MinBurnUpperBound")];
console.log("MinBurnUpperBound:", value.toHuman());
// Convert RAO to TAO if this is a balance value
const taoValue = value.toBigInt() / BigInt(1e9);
console.log("TAO:", taoValue.toString());Type Information
- Type
- u64
- Byte Size
- 8 bytes
- Encoding
- fixed
- Raw Hex
- 0x00ca9a3b00000000
Runtime Info
- Pallet
- SubtensorModule
- First Version
- v315
- Latest Version
- v315
- Current Runtime
- v393