diff --git a/collections/perf.sh b/collections/perf.sh
index 128343fc..a66101a0 100644
--- a/collections/perf.sh
+++ b/collections/perf.sh
@@ -22,7 +22,7 @@ let vector_rs = wasm_profiling("rust/.dfx/local/canisters/vector/vector.wasm", r
 //let movm_dynamic_rs = wasm_profiling("rust/.dfx/local/canisters/movm_dynamic/movm_dynamic.wasm");
 
 let file = "README.md";
-output(file, "\n## Map\n\n| |binary_size|generate 1m|max mem|batch_get 50|batch_put 50|batch_remove 50|upgrade|\n|--:|--:|--:|--:|--:|--:|--:|--:|\n");
+output(file, "\n## Map\n\n| |binary_size|generate 800k|max mem|batch_get 50|batch_put 50|batch_remove 50|upgrade|\n|--:|--:|--:|--:|--:|--:|--:|--:|\n");
 
 function perf(wasm, title, init, batch) {
   let cid = install(wasm, encode (), null);
@@ -59,7 +59,7 @@ function perf(wasm, title, init, batch) {
   uninstall(cid);
 };
 
-let init_size = 1_000_000;
+let init_size = 800_000;
 let batch_size = 50;
 
 perf(hashmap, "hashmap", init_size, batch_size);
@@ -73,7 +73,7 @@ perf(btreemap_stable_rs, "btreemap_stable_rs", init_size, batch_size);
 perf(imrc_hashmap_rs, "imrc_hashmap_rs", init_size, batch_size);
 perf(hashmap_rs, "hashmap_rs", init_size, batch_size);
 
-output(file, "\n## Priority queue\n\n| |binary_size|heapify 1m|max mem|pop_min 50|put 50|pop_min 50|upgrade|\n|--:|--:|--:|--:|--:|--:|--:|--:|\n");
+output(file, "\n## Priority queue\n\n| |binary_size|heapify 800k|max mem|pop_min 50|put 50|pop_min 50|upgrade|\n|--:|--:|--:|--:|--:|--:|--:|--:|\n");
 perf(heap, "heap", init_size, batch_size);
 perf(heap_rs, "heap_rs", init_size, batch_size);
 
diff --git a/collections/rust/src/btreemap_stable/src/lib.rs b/collections/rust/src/btreemap_stable/src/lib.rs
index 6d8843a1..15d4d268 100644
--- a/collections/rust/src/btreemap_stable/src/lib.rs
+++ b/collections/rust/src/btreemap_stable/src/lib.rs
@@ -26,7 +26,9 @@ fn generate(size: u32) {
 
 #[ic_cdk::query]
 fn get_mem() -> (u128, u128, u128) {
-    utils::get_mem()
+    let memory = ic_cdk::api::stable::CanisterStableMemory::Default();
+    let size = memory.stable_size() as u128;
+    (size, size, size)
 }
 
 #[ic_cdk::update]