add: Throughput testing helpers

crates/core/src/util/mod.rs

@@ -2,6 +2,7 @@ mod escape;
 mod fast_stack;
 mod gurantee;
 mod segment;
+mod throughput;
 
 #[allow(unused_imports)]
 pub use crate::util::escape::*;
@@ -14,3 +15,6 @@ pub use crate::util::gurantee::*;
 
 #[allow(unused_imports)]
 pub use crate::util::segment::*;
+
+#[allow(unused_imports)]
+pub use crate::util::throughput::*;

crates/core/src/util/throughput.rs

@@ -0,0 +1,47 @@
+use std::fmt::Display;
+
+pub struct Throughput {
+  rate: f64,
+  elapsed: std::time::Duration,
+}
+
+impl Display for Throughput {
+  #[inline(always)]
+  fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+    write!(f, "{}/s over {:.2}s", format_byte_size(self.rate), self.elapsed.as_secs_f64())
+  }
+}
+
+impl Throughput {
+  #[inline(always)]
+  pub fn compute<F>(iterations: usize, memory_baseline: usize, cb: F) -> Self
+  where
+    F: Fn(),
+  {
+    let now = std::time::Instant::now();
+    for _ in 0..iterations {
+      cb();
+    }
+    let elapsed = now.elapsed();
+    let memory_size = iterations * memory_baseline;
+
+    Self {
+      rate: memory_size as f64 / elapsed.as_secs_f64(),
+      elapsed,
+    }
+  }
+}
+
+#[inline(always)]
+fn format_byte_size(size: f64) -> String {
+  let units = ["B", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"];
+  let unit = 1000;
+  let mut size = size;
+  let mut i = 0;
+  while size > unit as f64 {
+    size /= unit as f64;
+    i += 1;
+  }
+
+  format!("{:.2} {}", size, units[i])
+}