Fix pallet_nis benchmark for Kusama runtime (#229)

Relates to: #223

A type alias `type Nis = pallet_balances::Pallet::<Runtime,
NisCounterpartInstance>;` for the second `pallet_balances` instance was
introduced [here](#58).
Unfortunately, nobody (including myself) realized that `Nis` is also
used for `[pallet_nis, Nis]`. As a result, the benchmark for
`pallet_nis` runs as if it were for `pallet_balances`, and the result
can be seen here:
[link](3bb9a02#diff-9bfa230a9b7f40866df3f84e81dfea72a64cc31bd9ef6e594c3d43582ba76522).

Therefore, this PR fixes this anomaly.

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Co-authored-by: fellowship-merge-bot[bot] <151052383+fellowship-merge-bot[bot]@users.noreply.github.com>

docs/weight-generation.md

@@ -67,7 +67,7 @@ for pallet in "${pallets[@]}"; do
 done
 ```
 
-You probably want to do this inside a `tmux` session or similar, as it will take a while.
+You probably want to do this inside a `tmux` session or something similar (e.g., `nohup <bench-cmd> &`), as it will take a while (several hours).
 
 7. `rsync` the weights back to your local machine, replacing the existing weights.
 
@@ -78,7 +78,20 @@ You probably want to do this inside a `tmux` session or similar, as it will take
 
 9. Commit the weight changes.
 
-10. If not installed, `cargo install subweight`, and check the weight changes with `subweight compare commits --path-pattern "./**/weights/*.rs" --method asymptotic --ignore-errors HEAD origin/main`. Ensure the changes are reasonable.
+10. Ensure the changes are reasonable. If not installed, `cargo install subweight`, check the weight changes:
+   ```
+   subweight compare commits \
+      --path-pattern "./**/weights/**/*.rs" \
+      --method asymptotic \
+      --ignore-errors \
+      <LATEST-RELEASE-BRANCH> \
+      <ACTUAL_BRANCH_WITH_COMMITED_WEIGHTS>`
+   ```
+   _Hint1: Add `--format markdown --no-color` for markdown-compatible results._
+
+   _Hint2: Change `--path-pattern "./**/weights/**/*.rs"` to e.g. `--path-pattern "./relay/polkadot/weights/**/*.rs"` for a specific runtime._
+
+   _Hint3: Add `--change added changed` to include only relevant changes._
 
 ## FAQ
 

relay/kusama/src/lib.rs

@@ -1477,7 +1477,7 @@ impl pallet_balances::Config<NisCounterpartInstance> for Runtime {
 	type MaxLocks = ConstU32<4>;
 	type MaxReserves = ConstU32<4>;
 	type ReserveIdentifier = [u8; 8];
-	type WeightInfo = weights::pallet_balances_nis::WeightInfo<Runtime>;
+	type WeightInfo = weights::pallet_balances_nis_counterpart::WeightInfo<Runtime>;
 	type RuntimeHoldReason = RuntimeHoldReason;
 	type RuntimeFreezeReason = RuntimeFreezeReason;
 	type FreezeIdentifier = ();
@@ -1981,7 +1981,7 @@ mod benches {
 		[runtime_parachains::coretime, Coretime]
 		// Substrate
 		[pallet_balances, Native]
-		[pallet_balances, Nis]
+		[pallet_balances, NisCounterpart]
 		[pallet_bags_list, VoterList]
 		[frame_benchmarking::baseline, Baseline::<Runtime>]
 		[pallet_bounties, Bounties]
@@ -2559,9 +2559,9 @@ sp_api::impl_runtime_apis! {
 			// Benchmark files generated for `Balances/NisCounterpartBalances` instances are by default
 			// `pallet_balances_balances.rs / pallet_balances_nis_counterpart_balances`, which is not really nice,
 			// so with this redefinition we can change names to nicer:
-			// `pallet_balances_native.rs / pallet_balances_nis.rs`.
+			// `pallet_balances_native.rs / pallet_balances_nis_counterpart.rs`.
 			type Native = pallet_balances::Pallet::<Runtime, ()>;
-			type Nis = pallet_balances::Pallet::<Runtime, NisCounterpartInstance>;
+			type NisCounterpart = pallet_balances::Pallet::<Runtime, NisCounterpartInstance>;
 
 			let mut list = Vec::<BenchmarkList>::new();
 			list_benchmarks!(list, extra);
@@ -2776,7 +2776,7 @@ sp_api::impl_runtime_apis! {
 			}
 
 			type Native = pallet_balances::Pallet::<Runtime, ()>;
-			type Nis = pallet_balances::Pallet::<Runtime, NisCounterpartInstance>;
+			type NisCounterpart = pallet_balances::Pallet::<Runtime, NisCounterpartInstance>;
 
 			let mut whitelist: Vec<TrackedStorageKey> = AllPalletsWithSystem::whitelisted_storage_keys();
 			let treasury_key = frame_system::Account::<Runtime>::hashed_key_for(Treasury::account_id());