工作單元，存儲庫，實體框架/達到最大池大小/平行foreach

Question

我有6000個項目和msSql上的每個項目進程並行foreach。 當我開始應用程序拋出一段時間後，達到最大池大小異常。 我試過MaxDegreeOfParallelism設置50，我沒有得到一個錯誤，但應用程序工作很慢。

我該怎麼辦這個錯誤。

我的代碼是這樣的;

using RPandUOW.EntityModel; 
using System; 
using System.Collections.Generic; 
using System.Data.Entity; 
using System.Linq; 
using System.Linq.Expressions; 

namespace RPandUOW.Repositories 
{ 
    public interface IGenericRepository<T> 
     where T:class 
    { 
     T FindById(object EntityId); 
     IEnumerable<T> Select(Expression<Func<T, bool>> Filter = null); 
     void Insert(T Entity); 
     void Update(T Entity); 
     void Delete(object EntityId); 
     void Delete(T Entity); 
    } 

    public class ShopRepository<T> 
     :IGenericRepository<T> 
     where T:class 
    { 
     private ShopContext _context; 
     private DbSet<T> _dbSet; 
     public ShopRepository(ShopContext Context) 
     { 
      _context = Context; 
      _dbSet = _context.Set<T>(); 
     } 
     public virtual T FindById(object EntityId) 
     { 
      return _dbSet.Find(EntityId); 
     } 
     public virtual IEnumerable<T> Select(Expression<Func<T, bool>> Filter = null) 
     { 
      if (Filter != null) 
      { 
       return _dbSet.Where(Filter); 
      } 
      return _dbSet; 
     } 
     public virtual void Insert(T entity) 
     { 
      _dbSet.Add(entity); 
     } 
     public virtual void Update(T entityToUpdate) 
     { 
      _dbSet.Attach(entityToUpdate); 
      _context.Entry(entityToUpdate).State = EntityState.Modified; 
     } 
     public virtual void Delete(object EntityId) 
     { 
      T entityToDelete = _dbSet.Find(EntityId); 
      Delete(entityToDelete); 
     } 
     public virtual void Delete(T Entity) 
     { 
      if (_context.Entry(Entity).State == EntityState.Detached) //Concurrency için 
      { 
       _dbSet.Attach(Entity); 
      } 
      _dbSet.Remove(Entity); 
     } 
    }} 

---

using RPandUOW.EntityModel; 
using RPandUOW.Repositories; 
using System; 
using System.Transactions; 

namespace RPandUOW.UnitOfWorks 
{ 
    public interface IUnitOfWork 
     :IDisposable 
    { 
     void Save(); 
     // Başka operasyonlar da tanımlanabilir. 
     // void OpenTransaction(); 
     // void CloseTransaction(); 
     // gibi 
    } 

    public class ShopUnitOfWork 
     :IUnitOfWork 
    { 
     private ShopContext _context = new ShopContext(); 
     private ShopRepository<Category> _categoryRepository; 
     private ShopRepository<Product> _productRepository; 
     private bool _disposed = false; 
     public ShopRepository<Category> CategoryRepository 
     { 
      get 
      { 
       if (_categoryRepository == null) 
        _categoryRepository = new ShopRepository<Category>(_context); 
       return _categoryRepository; 
      } 
     } 
     public ShopRepository<Product> ProductRepository 
     { 
      get 
      { 
       if (_productRepository == null) 
        _productRepository = new ShopRepository<Product>(_context); 
       return _productRepository; 
      } 
     } 
     public void Save() 
     { 
      using (TransactionScope tScope = new TransactionScope()) 
      { 
       _context.SaveChanges(); 
       tScope.Complete(); 
      } 
     } 
     protected virtual void Dispose(bool disposing) 
     { 
      if (!this._disposed) 
      { 
       if (disposing) 
       { 
        _context.Dispose(); 
       } 
      } 
      this._disposed = true; 
     } 
     public void Dispose() 
     { 
      Dispose(true); 
      GC.SuppressFinalize(this); 
     } 
    } 
} 

而且我有兩種方法這樣的原始SQL EXECUT：Context.Database.SqlQuery<string>(sqlQuery)

Parallel.ForEach(items, item => 
{ 
result = bl.run(item); 
}); 

Answer 1

您可以增加池的大小，增加並行線程數。

我還懷疑你的UoW/Repo模式可能存在實例/關閉問題。你如何實例化你的課程？更多的代碼會有幫助。