43d241c28d
- Add arena allocator for zero-allocation hot paths - Add thread pool for parallel operations - Add mmap utilities for memory-mapped I/O - Implement queue_index with heap-based priority queue - Implement dataset_hash with SIMD support (SHA-NI, ARMv8) - Add runtime SIMD detection for cross-platform correctness - Add comprehensive tests and benchmarks
53 lines
1.3 KiB
C++
53 lines
1.3 KiB
C++
#pragma once
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#include <condition_variable>
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#include <functional>
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#include <mutex>
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#include <queue>
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#include <thread>
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#include <vector>
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#include <cstdint>
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// Fixed-size thread pool for parallel operations.
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// Minimizes thread creation overhead for batch operations.
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class ThreadPool {
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std::vector<std::thread> workers_;
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std::queue<std::function<void()>> tasks_;
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std::mutex queue_mutex_;
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std::condition_variable condition_;
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bool stop_ = false;
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public:
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explicit ThreadPool(size_t num_threads);
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~ThreadPool();
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// Add task to queue. Thread-safe.
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void enqueue(std::function<void()> task);
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// Wait for all queued tasks to complete
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void wait_all();
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// Get optimal thread count (capped at 8 for I/O bound work)
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static uint32_t default_thread_count();
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};
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// Synchronization primitive: wait for N completions
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class CompletionLatch {
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std::atomic<size_t> count_{0};
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std::mutex mutex_;
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std::condition_variable cv_;
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public:
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explicit CompletionLatch(size_t total) : count_(total) {}
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void arrive() {
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if (--count_ == 0) {
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std::lock_guard<std::mutex> lock(mutex_);
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cv_.notify_all();
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}
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}
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void wait() {
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std::unique_lock<std::mutex> lock(mutex_);
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cv_.wait(lock, [&] { return count_.load() == 0; });
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}
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};
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