使用自定义序列化时出现OutOfMemory异常

本文关键字：OutOfMemory 异常 自定义 序列化 | 更新日期: 2023-09-27 18:13:08

在下面的代码中，我通过File对象的所有Block对象并执行基于bitconvert的序列化。在某些情况下，我有OutOfMemory异常。有什么方法可以优化它吗?

File.Serialze (); 

public byte[] Serialize()
{
    byte[] bytes = new byte[Blocks.Count * Block.Size];
    for (int i = 0; i < Blocks.Count; i++)
    {
        Block block = Blocks[i];
        Buffer.BlockCopy(block.Serialize(), 0, bytes, i * Block.Size, Block.Size);
    }
    return bytes;
}

Block.Serialize ()

public byte[] Serialize()
{
    byte[] bytes = new byte[Size];
    Buffer.BlockCopy(BitConverter.GetBytes(fid), 0, bytes, 0, sizeof(long));
    Buffer.BlockCopy(BitConverter.GetBytes(bid), 0, bytes, sizeof(long), sizeof(long));
    Buffer.BlockCopy(BitConverter.GetBytes(oid), 0, bytes, sizeof(long) * 2, sizeof(long));
    Buffer.BlockCopy(BitConverter.GetBytes(iid), 0, bytes, sizeof(long) * 3, sizeof(long));
    Buffer.BlockCopy(BitConverter.GetBytes(did), 0, bytes, sizeof(long) * 4, sizeof(long));
    return bytes;
}

MemoryStream而不是byte[]和shift而不是BitConverter.GetBytes()方法:

File.Serialize ()

public MemoryStream Serialize()
{
    MemoryStream fileMemoryStream = new MemoryStream(Blocks.Count * Block.Size);
    foreach (Block block in Blocks)
    {
        using (MemoryStream blockMemoryStream = block.Serialize())
        {
            blockMemoryStream.WriteTo(fileMemoryStream);
        }
    }
    return fileMemoryStream;
}

Block.Serialize ()

public MemoryStream Serialize()
{
    MemoryStream memoryStream = new MemoryStream(Size);
    memoryStream.Write(ConvertLongToByteArray(fid), 0, sizeof(long));
    memoryStream.Write(ConvertLongToByteArray(bid), 0, sizeof(long));
    memoryStream.Write(ConvertLongToByteArray(oid), 0, sizeof(long));
    memoryStream.Write(ConvertLongToByteArray(iid), 0, sizeof(long));
    memoryStream.Write(ConvertLongToByteArray(did), 0, sizeof(long));
    return memoryStream;
}
    private byte[] ConvertLongToByteArray(long number)
    {
        byte[] bytes = new byte[8];
        bytes[7] = (byte)((number >> 56) & 0xFF);
        bytes[6] = (byte)((number >> 48) & 0xFF);
        bytes[5] = (byte)((number >> 40) & 0XFF);
        bytes[4] = (byte)((number >> 32) & 0XFF);
        bytes[3] = (byte)((number >> 24) & 0xFF);
        bytes[2] = (byte)((number >> 16) & 0xFF);
        bytes[1] = (byte)((number >> 8) & 0XFF);
        bytes[0] = (byte)((number & 0XFF));
        return bytes;
    }

使用自定义序列化时出现OutOfMemory异常

我要问的第一个问题是:什么是Count和Size ?如果这些(当相乘时)很大，那么是的，它会消耗内存。当然，序列化到一个大缓冲区总是会导致问题。最好看看序列化到流的技术，这将允许使用单个中等大小的缓冲区。在您的情况下，也许每个"块"可以单独序列化并刷新到流中，然后重用相同的中等大小的缓冲区。就我个人而言，我尽量避免引入不必要的"块"——另一种技术是序列化到缓冲流，并让它决定何时刷新到底层流。

最后，它总是让我失望，BitConverter想要创建byte[]。写这个API的人需要好好谈谈。适当的技术应该是让API接受缓冲区和偏移量，并向现有缓冲区写入数据。拨款少得多。我建议寻找不使用所有这些分配(诚然是短暂的)的方法。这对于int/long等来说很容易(你只需要使用shift操作)，但是对于double等，你将需要不安全的代码或联合结构体。

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