diff --git a/Cargo.lock b/Cargo.lock
index 62adc83d..ec7a6dea 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -618,6 +618,7 @@ dependencies = [
  "color-backtrace",
  "criterion 0.4.0",
  "ctor 0.2.6",
+ "dev-utils",
  "flate2",
  "loro 0.16.2",
  "serde_json",
diff --git a/crates/dev-utils/src/lib.rs b/crates/dev-utils/src/lib.rs
index 16bed574..0927d72e 100644
--- a/crates/dev-utils/src/lib.rs
+++ b/crates/dev-utils/src/lib.rs
@@ -1,3 +1,4 @@
+use std::fmt::{Debug, Display};
 use std::path::Path;
 
 use tracing_subscriber::fmt::format::FmtSpan;
@@ -42,3 +43,62 @@ pub fn setup_test_log() {
         .unwrap();
     }
 }
+
+use std::alloc::{GlobalAlloc, Layout, System};
+use std::sync::atomic::{AtomicUsize, Ordering::Relaxed};
+
+struct Counter;
+
+static ALLOCATED: AtomicUsize = AtomicUsize::new(0);
+
+unsafe impl GlobalAlloc for Counter {
+    unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
+        let ret = System.alloc(layout);
+        if !ret.is_null() {
+            ALLOCATED.fetch_add(layout.size(), Relaxed);
+        }
+        ret
+    }
+
+    unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
+        System.dealloc(ptr, layout);
+        ALLOCATED.fetch_sub(layout.size(), Relaxed);
+    }
+}
+
+#[global_allocator]
+static A: Counter = Counter;
+
+pub struct MemorySize {
+    pub bytes: usize,
+}
+
+impl Debug for MemorySize {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let (size, unit) = match self.bytes {
+            bytes if bytes < 1024 => (bytes as f64, "B"),
+            bytes if bytes < 1024 * 1024 => (bytes as f64 / 1024.0, "KB"),
+            bytes if bytes < 1024 * 1024 * 1024 => (bytes as f64 / (1024.0 * 1024.0), "MB"),
+            bytes => (bytes as f64 / (1024.0 * 1024.0 * 1024.0), "GB"),
+        };
+        write!(f, "{:.2} {}", size, unit)
+    }
+}
+
+impl Display for MemorySize {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let (size, unit) = match self.bytes {
+            bytes if bytes < 1024 => (bytes as f64, "B"),
+            bytes if bytes < 1024 * 1024 => (bytes as f64 / 1024.0, "KB"),
+            bytes if bytes < 1024 * 1024 * 1024 => (bytes as f64 / (1024.0 * 1024.0), "MB"),
+            bytes => (bytes as f64 / (1024.0 * 1024.0 * 1024.0), "GB"),
+        };
+        write!(f, "{:.2} {}", size, unit)
+    }
+}
+
+pub fn get_allocated_bytes() -> MemorySize {
+    MemorySize {
+        bytes: ALLOCATED.load(Relaxed),
+    }
+}
diff --git a/crates/examples/Cargo.toml b/crates/examples/Cargo.toml
index 58378c07..ac901899 100644
--- a/crates/examples/Cargo.toml
+++ b/crates/examples/Cargo.toml
@@ -8,6 +8,7 @@ publish = false
 
 [dependencies]
 bench-utils = { path = "../bench-utils" }
+dev-utils = { path = "../dev-utils" }
 loro = { path = "../loro" }
 tabled = "0.15.0"
 arbitrary = { version = "1.3.0", features = ["derive"] }
diff --git a/crates/examples/examples/sheet.rs b/crates/examples/examples/sheet.rs
index e1266e9a..90eac82b 100644
--- a/crates/examples/examples/sheet.rs
+++ b/crates/examples/examples/sheet.rs
@@ -1,6 +1,16 @@
+use dev_utils::get_allocated_bytes;
 use examples::sheet::init_large_sheet;
 
 pub fn main() {
+    let allocated = get_allocated_bytes();
+    println!("allocated bytes: {}", allocated);
     let doc = init_large_sheet();
+    let allocated = get_allocated_bytes();
+    println!("allocated bytes: {}", allocated);
     doc.export_snapshot();
+    let allocated = get_allocated_bytes();
+    println!("allocated bytes: {}", allocated);
+    drop(doc);
+    let allocated = get_allocated_bytes();
+    println!("allocated bytes: {}", allocated);
 }