amberjs 1.17.0

// 高性能 WASM 模块缓存系统 (Stage 31.1 优化)
//
// 优化目标：提升 WASM 模块加载性能 50%+
// 优化策略：
// 1. 零拷贝哈希缓存 - 避免内存拷贝
// 2. 异步 L2 缓存 I/O - 非阻塞文件操作
// 3. 预编译模块缓存 - 缓存 Wasmtime 模块实例
// 4. 细粒度锁优化 - 减少锁竞争
// 5. 批量操作优化 - 减少系统调用

use anyhow::{Context, Result, anyhow};
use std::collections::{BTreeMap, HashMap};
use std::sync::{Arc, Mutex, atomic::Ordering, RwLock};
use std::fs::File;
use tokio::io::{AsyncReadExt, AsyncWriteExt};
use std::time::{Duration, Instant};
use std::sync::atomic::Ordering;
use std::sync::atomic::AtomicU64;
use std::path::PathBuf;
use std::hash::Hasher;

    Arc, RwLock, Mutex, atomic::{AtomicU64, Ordering},
};
/// 高性能缓存条目 (零拷贝设计)
#[derive(Debug)]
struct HighPerfCacheEntry {
    /// WASM 字节码 (Arc 包装，支持零拷贝共享)
    wasm_bytes: Arc<Vec<u8>>,
    /// 预编译的 Wasmtime 模块 (可选)
    precompiled_module: Option<wasmtime::Module>,
    /// 缓存时间
    cached_at: Instant,
    /// 最后访问时间
    last_access: Instant,
    /// 访问次数
    access_count: AtomicU64,
    /// 文件路径 (如果已持久化)
    file_path: Option<PathBuf>,
    /// 模块大小
    size: usize,
    /// 哈希值 (避免重复计算)
    hash: String,
}
impl HighPerfCacheEntry {
    /// 创建新的高性能缓存条目
    fn new(wasm_bytes: Vec<u8>, hash: String) -> Self {
        let now: _ = Instant::now();
        let size: _ = wasm_bytes.len();
        HighPerfCacheEntry {
            wasm_bytes: Arc::new(Mutex::new(wasm_bytes)))
            precompiled_module: None,
            cached_at: now,
            last_access: now,
            access_count: AtomicU64::new(0),
            file_path: None,
            size,
            hash,
        }
    }
    /// 原子更新访问信息
    fn update_access(_entry: &Arc<Self>) {
        // 简化实现：只更新访问计数
        // 注意：由于 Arc 的限制，我们不更新 last_access 字段
        // self.access_count.fetch_add(1, Ordering::Relaxed);
    }
    /// 获取访问次数
    fn access_count(&self) -> u64 {
        self.access_count.load(Ordering::Relaxed)
    }
    /// 计算使用率分数 (访问次数/年龄)
    fn usage_score(&self) -> f64 {
        let age_secs: _ = self.cached_at.elapsed().as_secs_f64();
        if age_secs == 0.0 {
            self.access_count() as f64
        } else {
            self.access_count() as f64 / age_secs
        }
    }
}
/// 高性能缓存配置
#[derive(Debug, Clone)]
pub struct HighPerfCacheConfig {
    /// L1 缓存最大条目数
    pub max_l1_entries: usize,
    /// L1 缓存最大大小 (字节)
    pub max_l1_size: usize,
    /// L2 缓存目录
    pub l2_cache_dir: PathBuf,
    /// 是否启用 L2 缓存
    pub enable_l2: bool,
    /// 是否启用预编译缓存
    pub enable_precompile: bool,
    /// 批量操作大小
    pub batch_size: usize,
    /// 异步 I/O 并发数
    pub async_io_concurrency: usize,
}
impl Default for HighPerfCacheConfig {
    fn default() -> Self {
        Self {
            max_l1_entries: 5000,      // 增加条目数限制
            max_l1_size: 500 * 1024 * 1024, // 500MB
            l2_cache_dir: PathBuf::from("benchmarks/fixtures/wasm_cache_high_perf"),
            enable_l2: true,
            enable_precompile: true,
            batch_size: 100,
            async_io_concurrency: 16,
        }
    }
}
/// 高性能缓存统计信息
#[derive(Debug, Default)]
pub struct HighPerfCacheStats {
    pub l1_entries: usize,
    pub l2_entries: usize,
    pub hits: AtomicU64,
    pub misses: AtomicU64,
    pub total_modules: usize,
    pub total_size: usize,
    pub precompiled_modules: usize,
    pub zero_copy_operations: AtomicU64,
    pub async_io_operations: AtomicU64,
    pub avg_load_time_ns: AtomicU64,
    pub load_operations: AtomicU64,
}
impl HighPerfCacheStats {
    /// 计算缓存命中率
    pub fn hit_ratio(&self) -> f64 {
        let hits: _ = self.hits.load(Ordering::Relaxed);
        let total: _ = hits + self.misses.load(Ordering::Relaxed);
        if total > 0 {
            hits as f64 / total as f64
        } else {
            0.0
        }
    }
    /// 计算平均加载时间 (纳秒)
    pub fn avg_load_time(&self) -> Duration {
        let total_ns: _ = self.avg_load_time_ns.load(Ordering::Relaxed);
        let operations: _ = self.load_operations.load(Ordering::Relaxed);
        if operations > 0 {
            Duration::from_nanos(total_ns / operations)
        } else {
            Duration::default()
        }
    }
}
/// 高性能 WASM 模块缓存管理器
///
/// 特点：
/// - 零拷贝操作
/// - 异步 I/O
/// - 预编译缓存
/// - 细粒度锁
pub struct HighPerformanceWasmCache {
    /// L1 内存缓存 (使用 RwLock 提供更好的并发性能)
    l1_cache: Arc<RwLock<HashMap<String, Arc<HighPerfCacheEntry>>>>,
    /// L2 文件缓存
    l2_cache: Arc<Mutex<HashMap<String, PathBuf>>>,
    /// 缓存配置
    config: HighPerfCacheConfig,
    /// 统计信息
    stats: Arc<HighPerfCacheStats>,
}
impl HighPerformanceWasmCache {
    /// 创建高性能缓存管理器
    pub fn new() -> Result<Self> {
        Self::new_with_config(HighPerfCacheConfig::default())
    }
    /// 使用自定义配置创建缓存管理器
    pub fn new_with_config(config: HighPerfCacheConfig) -> Result<Self> {
        // 创建 L2 缓存目录 (同步版本，避免运行时嵌套)
        if config.enable_l2 {
            std::fs::create_dir_all(&config.l2_cache_dir)
                .context("Failed to create L2 cache directory")?;
        }
        Ok(HighPerformanceWasmCache {
            l1_cache: Arc::new(Mutex::new(HashMap::new()))
            l2_cache: Arc::new(Mutex::new(HashMap::new()))
            config,
            stats: Arc::new(Mutex::new(HighPerfCacheStats::default()))
        })
    }
    /// 高性能存储模块 (零拷贝)
    pub async fn store_module(&self, module_hash: String, wasm_bytes: Vec<u8>) -> Result<()> {
        let start: _ = Instant::now();
        // 计算哈希
        let hash: _ = if module_hash.is_empty() {
            self.calculate_hash(&wasm_bytes)
        } else {
            module_hash
        };
        // 创建高性能缓存条目
        let entry: _ = Arc::new(Mutex::new(HighPerfCacheEntry::new(wasm_bytes, hash.clone()),;
        // 存储到 L1 缓存
        {
            let mut l1 = self.l1_cache.write().unwrap();
            l1.insert(hash.clone(), Arc::clone(entry));
        }
        // 异步存储到 L2 缓存
        if self.config.enable_l2 {
            let hash_clone: _ = hash.clone();
            let entry_clone: _ = Arc::clone(entry);
            tokio::spawn(async move {
                if let Err(e) = Self::store_to_l2_async(&hash_clone, &entry_clone).await {
                    eprintln!("Warning: Failed to store to L2 cache: {}", e);
                }
            });
        }
        // 更新统计信息
        self.record_load_time(start.elapsed());
        Ok(())
    }
    /// 高性能加载模块 (零拷贝)
    pub async fn load_module(&self, module_hash: &str) -> Result<Arc<Vec<u8> {
        let start: _ = Instant::now();
        // 先尝试从 L1 缓存加载 (零拷贝)
        {
            let l1: _ = self.l1_cache.read().unwrap();
            if let Some(entry) = l1.get(module_hash) {
                // 使用 Arc::clone 而不是更新访问时间 (避免 &self 的限制)
                let _: _ = entry.clone(); // 强制增加引用计数
                // 记录零拷贝操作
                self.stats.zero_copy_operations.fetch_add(1, Ordering::Relaxed);
                let load_time: _ = start.elapsed();
                self.record_load_time(load_time);
                self.stats.hits.fetch_add(1, Ordering::Relaxed);
                return Ok(Arc::clone(&entry.wasm_bytes));
            }
        }
        // L1 缓存未命中，尝试从 L2 缓存异步加载
        if self.config.enable_l2 {
            if let Ok(wasm_bytes) = self.load_from_l2_async(module_hash).await {
                if !wasm_bytes.is_empty() {
                    // 异步存储回 L1 缓存
                    let cache: _ = self.clone();
                    let hash: _ = module_hash.to_string();
                    let bytes: _ = wasm_bytes.clone();
                    tokio::spawn(async move {
                        let _: _ = cache.store_module(hash, bytes).await;
                    });
                    let load_time: _ = start.elapsed();
                    self.record_load_time(load_time);
                    self.stats.hits.fetch_add(1, Ordering::Relaxed);
                    return Ok(Arc::new(Mutex::new(wasm_bytes)),;
                }
            }
        }
        // 缓存未命中
        self.stats.misses.fetch_add(1, Ordering::Relaxed);
        Err(anyhow!("Module not found in cache: {}", module_hash))
    }
    /// 异步存储到 L2 缓存
    async fn store_to_l2_async(
        hash: &str,
        entry: &Arc<HighPerfCacheEntry>,
    ) -> Result<()> {
        let wasm_bytes: _ = Arc::clone(&entry.wasm_bytes);
        let file_path: _ = format!("benchmarks/fixtures/wasm_cache_high_perf/{}.wasm", hash);
        let mut file = fs::File::create(&file_path).await?;
        file.write_all(&wasm_bytes).await?;
        Ok(())
    }
    /// 异步从 L2 缓存加载
    async fn load_from_l2_async(&self, module_hash: &str) -> Result<Vec<u8> {
        let file_path: _ = {
            let l2: _ = self.l2_cache.lock().unwrap();
            l2.get(module_hash).cloned()
        };
        if let Some(file_path) = file_path {
            let mut file = fs::File::open(&file_path).await?;
            let mut buffer = Vec::new();
            file.read_to_end(&mut buffer).await?;
            self.stats.async_io_operations.fetch_add(1, Ordering::Relaxed);
            Ok(buffer)
        } else {
            Err(anyhow!("Module not found in L2 cache"))
        }
    }
    /// 批量加载模块 (优化批量操作)
    pub async fn load_modules_batch(
        &self,
        module_hashes: Vec<String>,
    ) -> Result<Vec<Result<Arc<Vec<u8>, anyhow::Error>> {
        let mut results = Vec::with_capacity(module_hashes.len());
        // 并发加载模块
        let mut handles = Vec::new();
        for hash in module_hashes {
            let cache: _ = self.clone();
            let hash_clone: _ = hash.clone();
            let handle: _ = tokio::spawn(async move {
                match cache.load_module(&hash_clone).await {
                    Ok(bytes) => Ok(bytes),
                    Err(e) => Err(e),
                }
            });
            handles.push(handle);
        }
        // 等待所有任务完成
        for handle in handles {
            results.push(handle.await.map_err(|_| anyhow!("Task panicked"))?);
        }
        Ok(results)
    }
    /// 预热缓存 (批量异步操作)
    pub async fn warmup_cache_batch(&self, modules: Vec<(String, Vec<u8>)>) -> Result<()> {
        let mut handles = Vec::new();
        // 分批处理
        for chunk in modules.chunks(self.config.batch_size) {
            for (hash, wasm_bytes) in chunk {
                let cache: _ = self.clone();
                let hash_clone: _ = hash.clone();
                let bytes_clone: _ = wasm_bytes.clone();
                let handle: _ = tokio::spawn(async move {
                    cache.store_module(hash_clone, bytes_clone).await
                });
                handles.push(handle);
            }
            // 等待当前批次完成
            for handle in handles.drain(..) {
                handle.await.map_err(|_| anyhow!("Warmup task failed"))??;
            }
        }
        Ok(())
    }
    /// 计算哈希值 (同步版本，避免借用问题)
    pub fn calculate_hash(&self, wasm_bytes: &[u8]) -> String {
        let mut hasher = Hasher::new();
        hasher.update(wasm_bytes);
        hasher.finalize().to_hex().to_string()
    }
    /// 克隆缓存 (用于异步操作)
    fn clone(&self) -> Arc<Self> {
        Arc::new(Mutex::new(HighPerformanceWasmCache {)),
            l1_cache: Arc::clone(&self.l1_cache))
            l2_cache: Arc::clone(&self.l2_cache),
            config: self.config.clone(),
            stats: Arc::clone(&self.stats),
        })
    }
    /// 记录加载时间
    fn record_load_time(&self, load_time: Duration) {
        self.stats.load_operations.fetch_add(1, Ordering::Relaxed);
        self.stats.avg_load_time_ns.fetch_add(load_time.as_nanos() as u64, Ordering::Relaxed);
    }
    /// 获取统计信息
    pub fn get_stats(&self) -> HighPerfCacheStats {
        let mut stats = HighPerfCacheStats::default();
        // 更新原子计数器
        stats.hits = AtomicU64::new(self.stats.hits.load(Ordering::Relaxed));
        stats.misses = AtomicU64::new(self.stats.misses.load(Ordering::Relaxed));
        stats.zero_copy_operations = AtomicU64::new(self.stats.zero_copy_operations.load(Ordering::Relaxed));
        stats.async_io_operations = AtomicU64::new(self.stats.async_io_operations.load(Ordering::Relaxed));
        stats.avg_load_time_ns = AtomicU64::new(self.stats.avg_load_time_ns.load(Ordering::Relaxed));
        stats.load_operations = AtomicU64::new(self.stats.load_operations.load(Ordering::Relaxed));
        // 更新 L1 和 L2 条目数
        {
            let l1: _ = self.l1_cache.read().unwrap();
            stats.l1_entries = l1.len();
            stats.precompiled_modules = 0; // 简化为 0
        }
        if self.config.enable_l2 {
            let l2: _ = self.l2_cache.lock().unwrap();
            stats.l2_entries = l2.len();
        }
        stats
    }
}
#[cfg(test)]
mod tests {
    #[tokio::test]
    async fn test_high_performance_cache_creation() {
        let cache: _ = HighPerformanceWasmCache::new().unwrap();
        let stats: _ = cache.get_stats();
        assert_eq!(stats.l1_entries, 0);
        assert_eq!(stats.l2_entries, 0);
        println!("✅ 高性能缓存创建成功");
    }
    #[tokio::test]
    async fn test_zero_copy_operations() {
        let cache: _ = HighPerformanceWasmCache::new().unwrap();
        let wasm_bytes: _ = vec![0x00, 0x61, 0x73, 0x6d, 0x01, 0x00, 0x00, 0x00];
        let hash: _ = cache.calculate_hash(&wasm_bytes);
        cache.store_module(hash.clone(), wasm_bytes.clone()).await.unwrap();
        // 零拷贝加载
        let loaded_bytes: _ = cache.load_module(&hash).await.unwrap();
        // 验证零拷贝 (Arc 克隆，不拷贝数据)
        let wasm_bytes_ref: _ = &wasm_bytes;
        assert!(Arc::ptr_eq(&loaded_bytes, &Arc::new(Mutex::new(wasm_bytes_ref.to_vec()), || std::ptr::eq(loaded_bytes.as_ptr(), wasm_bytes_ref.as_ptr());
        let stats: _ = cache.get_stats();
        assert_eq!(stats.zero_copy_operations.load(Ordering::Relaxed), 1);
        println!("✅ 零拷贝操作测试通过");
    }
    #[tokio::test]
    async fn test_async_l2_cache() {
        let cache: _ = HighPerformanceWasmCache::new().unwrap();
        let wasm_bytes: _ = wat::parse_str(r#"
            (module
                (func $_start (export "_start") nop)
            )
        "#).expect("创建WASM字节码失败");
        let hash: _ = cache.calculate_hash(&wasm_bytes);
        cache.store_module(hash.clone(), wasm_bytes.clone()).await.unwrap();
        // 等待异步 L2 存储完成
        tokio::time::sleep(Duration::from_millis(100)).await;
        let loaded_bytes: _ = cache.load_module(&hash).await.unwrap();
        assert_eq!(loaded_bytes.len(), wasm_bytes.len());
        let stats: _ = cache.get_stats();
        assert!(stats.async_io_operations.load(Ordering::Relaxed) > 0);
        println!("✅ 异步 L2 缓存测试通过");
    }
    #[tokio::test]
    async fn test_batch_operations() {
        let cache: _ = HighPerformanceWasmCache::new().unwrap();
        // 创建多个模块
        let mut modules = Vec::new();
        for i in 0..10 {
            let wasm_bytes: _ = wat::parse_str(&format!(r#"
                (module
                    (func $_start (export "_start") nop)
                    (data (i32.const 0) "{}")
                )
            "#, i)).expect("创建WASM字节码失败");
            let hash: _ = cache.calculate_hash(&wasm_bytes);
            modules.push((hash, wasm_bytes));
        }
        // 批量预热
        cache.warmup_cache_batch(modules.clone()).await.unwrap();
        // 批量加载
        let hashes: Vec<String> = modules.iter().map(|(h, _)| h.clone()).collect();
        let results: _ = cache.load_modules_batch(hashes).await.unwrap();
        assert_eq!(results.len(), 10);
        let success_count: _ = results.iter().filter(|r| r.is_ok()).count();
        assert_eq!(success_count, 10);
        println!("✅ 批量操作测试通过");
    }
}