gpu/test_realistic_perf.go

//go:build ignore
// +build ignore

package main

import (
	"fmt"
	"github.com/luxfi/gpu"
	"time"
)

func main() {
	fmt.Println("=== GPU Realistic Performance Test ===")
	fmt.Printf("System: %s\n\n", gpu.Info())

	// Compare backends
	backends := []struct {
		backend gpu.Backend
		name    string
	}{
		{gpu.Metal, "Metal (GPU)"},
		{gpu.CPU, "CPU"},
	}

	for _, b := range backends {
		err := gpu.SetBackend(b.backend)
		if err != nil {
			fmt.Printf("%s: Not available\n\n", b.name)
			continue
		}

		fmt.Printf("Testing %s Backend:\n", b.name)

		// Large matrix for realistic timing
		size := 2000
		fmt.Printf("  Matrix size: %dx%d\n", size, size)

		// Create matrices
		a := gpu.Random([]int{size, size}, gpu.Float32)
		b := gpu.Random([]int{size, size}, gpu.Float32)

		// Single operation timing
		start := time.Now()
		c := gpu.MatMul(a, b)
		gpu.Eval(c)
		gpu.Synchronize()
		elapsed := time.Since(start)

		// Calculate performance
		ops := int64(size) * int64(size) * int64(size) * 2 // multiply-add
		gflops := float64(ops) / elapsed.Seconds() / 1e9
		bandwidth := float64(size*size*4*3) / elapsed.Seconds() / 1e9 // 3 matrices, 4 bytes each

		fmt.Printf("  Time: %.1f ms\n", elapsed.Seconds()*1000)
		fmt.Printf("  Performance: %.1f GFLOPS\n", gflops)
		fmt.Printf("  Memory bandwidth: %.1f GB/s\n", bandwidth)
		fmt.Println()

		// Clean up
		gpu.DefaultContext.Free(c)
	}

	// Reset to auto
	gpu.SetBackend(gpu.Auto)
	fmt.Printf("Auto-detection selected: %s\n", gpu.GetBackend())
	fmt.Println("This is the optimal backend for your M-series Mac!")
}