chore: Add fuzz test for memory manager on stable structures

benchmark-canisters/src/memory_manager.rs

@@ -5,6 +5,7 @@ use ic_stable_structures::{DefaultMemoryImpl, Memory};
 const WASM_PAGE_SIZE: usize = 65536;
 const MB: usize = 1024 * 1024;
 const MB_IN_PAGES: usize = MB / WASM_PAGE_SIZE;
+const BUCKET_SIZE_IN_PAGES: u64 = 128;
 
 /// Benchmarks accessing stable memory without using a `MemoryManager` to establish a baseline.
 #[ic_cdk_macros::query]
@@ -56,3 +57,21 @@ pub fn memory_manager_overhead() -> BenchResult {
         }
     })
 }
+
+/// Benchmarks the `MemoryManager` by allocating a large number of buckets.
+#[ic_cdk_macros::query]
+pub fn memory_manager_buckets_allocation() -> BenchResult {
+    let mem_mgr = MemoryManager::init(DefaultMemoryImpl::default());
+
+    let num_memories = 5;
+    let buckets_per_memory = 200;
+
+    crate::benchmark(|| {
+        for i in 0..num_memories {
+            let memory = mem_mgr.get(MemoryId::new(i));
+            for _ in 0..buckets_per_memory {
+                memory.grow(BUCKET_SIZE_IN_PAGES);
+            }
+        }
+    })
+}

benchmarks/benchmark.rs

@@ -22,6 +22,7 @@ lazy_static::lazy_static! {
         // MemoryManager benchmarks
         "memory_manager_baseline",
         "memory_manager_overhead",
+        "memory_manager_buckets_allocation",
 
         // BTree benchmarks
         "btreemap_insert_10mib_values",