Add some metal gemm benchark. (#2471)

* Add some metal gemm benchark.

* More benchmarks.

candle-metal-kernels/Cargo.toml

@@ -17,10 +17,12 @@ thiserror = "1"
 tracing = "0.1.37"
 
 [dev-dependencies]
+clap = { version = "4.2.4", features = ["derive"] }
 half = { version = "2.3.1", features = [
   "num-traits",
   "use-intrinsics",
   "rand_distr",
 ] }
+anyhow = "1"
 rand = "0.8.5"
 rand_distr = "0.4.3"

candle-metal-kernels/examples/metal_benchmarks.rs

@@ -0,0 +1,136 @@
+use anyhow::Result;
+use candle_metal_kernels::GemmDType;
+/// This example contains some simple benchmarks so that it's easy to run them in perf etc.
+use clap::{Parser, Subcommand};
+use half::f16;
+
+fn run_gemm(f32: bool, n: usize) -> Result<()> {
+    const WARMUP_ITERS: usize = 2;
+    const MIN_DUR: f64 = 4.;
+
+    let device = metal::Device::system_default().unwrap();
+
+    let (b, m, n, k) = (1, n, n, n);
+    let kernels = candle_metal_kernels::Kernels::new();
+    let command_queue = device.new_command_queue();
+    let options = metal::MTLResourceOptions::StorageModeManaged;
+
+    let (lhs, rhs) = if f32 {
+        let lhs: Vec<f32> = (0..b * m * k).map(|f| f as f32).collect();
+        let rhs: Vec<f32> = (0..b * n * k).map(|f| f as f32).collect();
+        let lhs = device.new_buffer_with_data(
+            lhs.as_ptr() as *const core::ffi::c_void,
+            std::mem::size_of_val(&lhs) as u64,
+            options,
+        );
+        let rhs = device.new_buffer_with_data(
+            rhs.as_ptr() as *const core::ffi::c_void,
+            std::mem::size_of_val(&rhs) as u64,
+            options,
+        );
+        (lhs, rhs)
+    } else {
+        let lhs: Vec<f16> = (0..b * m * k).map(|f| f16::from_f32(f as f32)).collect();
+        let rhs: Vec<f16> = (0..b * n * k).map(|f| f16::from_f32(f as f32)).collect();
+        let lhs = device.new_buffer_with_data(
+            lhs.as_ptr() as *const core::ffi::c_void,
+            std::mem::size_of_val(&lhs) as u64,
+            options,
+        );
+        let rhs = device.new_buffer_with_data(
+            rhs.as_ptr() as *const core::ffi::c_void,
+            std::mem::size_of_val(&rhs) as u64,
+            options,
+        );
+        (lhs, rhs)
+    };
+    let (dtype, name, sizeof) = if f32 {
+        (GemmDType::F32, "sgemm", core::mem::size_of::<f32>())
+    } else {
+        (GemmDType::F16, "hgemm", core::mem::size_of::<f16>())
+    };
+    let output = device.new_buffer((b * m * n * sizeof) as u64, options);
+
+    for mlx in [false, true] {
+        let mut sum_dt = 0f64;
+        let mut iters = 0usize;
+        for idx in 0.. {
+            let command_buffer = command_queue.new_command_buffer();
+            let start_time = std::time::Instant::now();
+            if mlx {
+                candle_metal_kernels::call_mlx_gemm(
+                    &device,
+                    command_buffer,
+                    &kernels,
+                    dtype,
+                    (b, m, n, k),
+                    &[m * k, k, 1],
+                    0,
+                    &lhs,
+                    &[n * k, n, 1],
+                    0,
+                    &rhs,
+                    &output,
+                )?;
+            } else {
+                candle_metal_kernels::call_gemm(
+                    &device,
+                    command_buffer,
+                    &kernels,
+                    name,
+                    (b, m, n, k),
+                    &[m * k, k, 1],
+                    0,
+                    &lhs,
+                    &[n * k, n, 1],
+                    0,
+                    &rhs,
+                    &output,
+                )?;
+            }
+            command_buffer.commit();
+            command_buffer.wait_until_completed();
+            let dt = start_time.elapsed().as_secs_f64();
+            if idx < WARMUP_ITERS {
+                continue;
+            }
+            sum_dt += dt;
+            iters += 1;
+            if sum_dt > MIN_DUR {
+                break;
+            }
+        }
+        let gflops = (2 * n * n * n * iters) as f64 / (1e9 * sum_dt);
+        let mlx = if mlx { "MLX" } else { "MFA" };
+        println!("{mlx} {dtype:?},      {n:6}      gflops {gflops:.0}");
+    }
+
+    Ok(())
+}
+
+#[derive(Subcommand, Debug, Clone)]
+enum Task {
+    Gemm,
+}
+
+#[derive(Parser, Debug)]
+#[command(author, version, about, long_about = None)]
+pub struct Args {
+    /// The benchmark to be run.
+    #[command(subcommand)]
+    task: Task,
+}
+
+fn main() -> Result<()> {
+    let args = Args::parse();
+    match args.task {
+        Task::Gemm => {
+            for f32 in [false, true] {
+                for n in [512, 1024, 2048, 4096] {
+                    run_gemm(f32, n)?;
+                }
+            }
+        }
+    }
+    Ok(())
+}