This error was removed in v150

This error is no longer present in the current runtime. Existed from v101 to v150. Shown here for historical reference.

MaxAllowedUIdsNotAllowed

Error Removed v101 → v117, v118 → v120, v121 → v127, v133 → v141, v142 → v150 (removed) 7.22

The subnet has reached its maximum capacity for registered neurons.

Encountered by: minersvalidatorsdevelopers

Why This Error Exists

Each subnet has a maximum number of UIDs it can support, set by the subnet owner. When full, new registrations must wait for pruning - the automatic removal of neurons with the lowest stake or performance. Popular subnets often hit this limit, creating competition for slots.

Deep Dive

SubnetworkN tracks current neuron count. MaxAllowedUids is the cap. When SubnetworkN >= MaxAllowedUids, new registrations trigger pruning: the neuron with lowest stake/trust is replaced. If YOUR stake is lower than the minimum existing stake, you might register but immediately get pruned yourself. Check MinAllowedWeights and current stake distribution to assess competition.

Debugging Example

You call burned_register(netuid=1, ...). Error: MaxAllowedUIdsNotAllowed. Query SubnetworkN(1) - returns 256. Query MaxAllowedUids(1) - returns 256. Subnet is at capacity. Check Neurons(1, 0..255) to find the minimum stake. If you stake MORE than that minimum, you might succeed in replacing the weakest neuron on next attempt.

Prevention Tips

  • Check SubnetworkN vs MaxAllowedUids before registration attempts
  • Stake significantly above the subnet's minimum to avoid being pruned
  • Consider less competitive subnets if you're starting with low stake

What This Means

The subnet has reached its maximum capacity for registered neurons.

Common Causes

  • Subnet is full
  • No slots available for new registrations
  • Must wait for deregistrations to free slots

How to Fix

  • Check SubtensorModule.SubnetworkN for current count
  • Compare against SubtensorModule.MaxAllowedUids for capacity
  • Wait for low-performing neurons to be pruned

Storage to Check

Version History

v101 block 1 Added
v118 block 222,600 Re-added
v121 block 518,345 Re-added
v133 block 1,404,224 Re-added
v142 block 2,543,779 Re-added
v150 Removed

Runtime Info

Pallet Index
7
Error Index
22
Error Code
7.22
Removed In
v150