add a global min burn and migration

Author: camfairchild

pallets/admin-utils/src/tests/mock.rs

@@ -100,7 +100,7 @@ parameter_types! {
     pub const InitialTxDelegateTakeRateLimit: u64 = 0; // Disable rate limit for testing
     pub const InitialTxChildKeyTakeRateLimit: u64 = 0; // Disable rate limit for testing
     pub const InitialBurn: u64 = 0;
-    pub const InitialMinBurn: u64 = 0;
+    pub const InitialMinBurn: u64 = 500_000;
     pub const InitialMaxBurn: u64 = 1_000_000_000;
     pub const InitialValidatorPruneLen: u64 = 0;
     pub const InitialScalingLawPower: u16 = 50;

pallets/subtensor/src/macros/hooks.rs

@@ -79,7 +79,9 @@ mod hooks {
 				.saturating_add(migrations::migrate_fix_is_network_member::migrate_fix_is_network_member::<T>())
 				.saturating_add(migrations::migrate_subnet_volume::migrate_subnet_volume::<T>())
                 // Upgrade identities to V2
-                .saturating_add(migrations::migrate_identities_v2::migrate_identities_to_v2::<T>());
+                .saturating_add(migrations::migrate_identities_v2::migrate_identities_to_v2::<T>())
+				// Set the min burn across all subnets to a new minimum
+				.saturating_add(migrations::migrate_set_min_burn::migrate_set_min_burn::<T>());
             weight
         }
 

pallets/subtensor/src/migrations/migrate_set_min_burn.rs

@@ -0,0 +1,52 @@
+use alloc::string::String;
+
+use frame_support::IterableStorageMap;
+use frame_support::{traits::Get, weights::Weight};
+
+use super::*;
+
+pub fn migrate_set_min_burn<T: Config>() -> Weight {
+    let migration_name = b"migrate_set_min_burn".to_vec();
+
+    // Initialize the weight with one read operation.
+    let mut weight = T::DbWeight::get().reads(1);
+
+    // Check if the migration has already run
+    if HasMigrationRun::<T>::get(&migration_name) {
+        log::info!(
+            "Migration '{:?}' has already run. Skipping.",
+            migration_name
+        );
+        return weight;
+    }
+    log::info!(
+        "Running migration '{}'",
+        String::from_utf8_lossy(&migration_name)
+    );
+
+    let netuids: Vec<u16> = <NetworksAdded<T> as IterableStorageMap<u16, bool>>::iter()
+        .map(|(netuid, _)| netuid)
+        .collect();
+    weight = weight.saturating_add(T::DbWeight::get().reads(netuids.len() as u64));
+
+    for netuid in netuids.iter().clone() {
+        if *netuid == 0 {
+            continue;
+        }
+        // Set min burn to the newest initial min burn
+        Pallet::<T>::set_min_burn(*netuid, T::InitialMinBurn::get());
+        weight = weight.saturating_add(T::DbWeight::get().writes(1));
+    }
+
+    // Mark the migration as completed
+    HasMigrationRun::<T>::insert(&migration_name, true);
+    weight = weight.saturating_add(T::DbWeight::get().writes(1));
+
+    log::info!(
+        "Migration '{:?}' completed.",
+        String::from_utf8_lossy(&migration_name)
+    );
+
+    // Return the migration weight.
+    weight
+}

pallets/subtensor/src/migrations/mod.rs

@@ -11,6 +11,7 @@ pub mod migrate_init_total_issuance;
 pub mod migrate_populate_owned_hotkeys;
 pub mod migrate_populate_staking_hotkeys;
 pub mod migrate_rao;
+pub mod migrate_set_min_burn;
 pub mod migrate_stake_threshold;
 pub mod migrate_subnet_volume;
 pub mod migrate_to_v1_separate_emission;