diff --git a/bencher/src/handler.rs b/bencher/src/handler.rs
index 79cc8c9ec..2657071a9 100644
--- a/bencher/src/handler.rs
+++ b/bencher/src/handler.rs
@@ -54,6 +54,9 @@ pub fn handle(output: Vec<u8>, storage_infos: Vec<StorageInfo>) {
 					let name = String::from_utf8(info.storage_name.clone()).unwrap();
 					let comment = format!("{}::{} (r: {}, w: {})", pallet, name, reads, writes);
 					comments.push(comment);
+				} else {
+					let comment = format!("Unknown (r: {}, w: {})", reads, writes);
+					comments.push(comment);
 				}
 			});
 
diff --git a/bencher/src/tracker.rs b/bencher/src/tracker.rs
index 44032eafb..e5345ef12 100644
--- a/bencher/src/tracker.rs
+++ b/bencher/src/tracker.rs
@@ -217,7 +217,8 @@ impl BenchTracker {
 		let mut summary = HashMap::<StorageKey, AccessReport>::new();
 
 		self.main_keys.read().iter().for_each(|(key, info)| {
-			let prefix = key[0..32].to_vec();
+			let prefix_end = core::cmp::min(32, key.len());
+			let prefix = key[0..prefix_end].to_vec();
 			if let Some(report) = summary.get_mut(&prefix) {
 				if info.read.is_important() {
 					report.read += 1;
@@ -241,7 +242,8 @@ impl BenchTracker {
 
 		self.child_keys.read().iter().for_each(|(prefix, keys)| {
 			keys.iter().for_each(|(key, info)| {
-				let prefix = [prefix.clone(), key.clone()].concat()[0..32].to_vec();
+				let prefix_end = core::cmp::min(32, prefix.len() + key.len());
+				let prefix = [prefix.clone(), key.clone()].concat()[0..prefix_end].to_vec();
 				if let Some(report) = summary.get_mut(&prefix) {
 					if info.read.is_important() {
 						report.read += 1;
diff --git a/bencher/test/src/mock.rs b/bencher/test/src/mock.rs
index 0c18524ba..375044a1a 100644
--- a/bencher/test/src/mock.rs
+++ b/bencher/test/src/mock.rs
@@ -1,5 +1,6 @@
 #![cfg(any(test, feature = "bench"))]
 
+use frame_support::pallet_prelude::ConstU32;
 use sp_core::H256;
 use sp_runtime::{
 	traits::{BlakeTwo256, IdentityLookup},