Call Workflow
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The Big Picture
Creating a subnet doesn't automatically start it. start_call is the 'go live' button - it activates emissions and marks the subnet as operational. This separation allows owners to configure parameters, attract initial miners, and test before going live with real incentives.
Why This Matters
Starting a subnet with no miners is wasteful - emissions have nowhere to go. The delayed start lets you set up properly. Advertise your subnet, onboard initial participants, configure parameters, then call start_call when ready.
Example Scenario
You created subnet 47 and spent a week onboarding 50 miners and 5 validators. Parameters are set, everything is tested. Call start_call(netuid=47). FirstEmissionBlockNumber is set to the current block. From now on, your subnet receives emissions and participants can earn.
Common Questions
- What if I start too early?
- Emissions go to whoever is registered. With few miners, they get concentrated rewards. With no miners, emissions might be wasted. Start when you have enough participation.
- Can I pause after starting?
- Not typically - start_call is a one-way activation. Once started, the subnet runs until dissolution. Plan your launch timing carefully.
- Do I have to start manually?
- For owned subnets, usually yes. Some subnet types might auto-start after conditions are met. Check your subnet's configuration.
Use Cases
- Activate a newly created subnet after setup is complete
- Begin emissions after configuration and testing
- Launch subnet operations after gathering initial participants
- Signal subnet readiness to the network
From Chain Metadata
Initiates a call on a subnet.
Input Parameters
| # | Name | Type | Description |
|---|---|---|---|
| 0 | netuid | u16 | Subnet/network identifier (0-65535) |
Permissions
Permission data inferred from metadata. May be incomplete.
Requirements
- Subnet exists
- Start conditions met (minimum neurons, configuration complete)
- Caller is subnet owner or admin
Effects
Events Emitted
Storage Modified
Postconditions
- FirstEmissionBlockNumber set
- Subnet begins receiving emissions
- Subnet becomes active in network
Side Effects
- Activates subnet in emission distribution
- Miners and validators can start earning
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 });
// Build start_call call
const netuid = 1;
const call = api.tx[stringCamelCase("SubtensorModule")][stringCamelCase("start_call")](
netuid
);Runtime Info
View Source- Pallet Index
- 7
- Call Index
- 92
- First Version
- v257
- Current Version
- v393