c++ - Boost 序列化和文件 IO 非常慢

Question

我正在制作一个游戏并且有一个资源文件格式来加载 3d 模型，纹理和网格等定义如下:

/* PackageHeader definition */
    struct PackageHeader
    {
        std::string mSignature;
        uint8_t mMajorVersion;
        uint8_t mMinorVersion;


        PackageHeader();
    };

    /* PackageMesh definition */
    struct PackageMesh
    {
        std::vector<Vec3> mVertexData;
        std::vector<Vec3> mNormalData;
        std::vector<Vec2> mTexCoordsData;
        std::vector<uint32_t> mIndiceData;
        uint16_t mMaterialIndex;
        bool mHasMaterial;


        PackageMesh();
    };

    /* PackageTexture definition */
    struct PackageTexture
    {
        std::string mName;
        std::vector<uint8_t> mTextureData;
        uint32_t mTextureWidth;         // width/height in pixels
        uint32_t mTextureHeight;
        ITexture::TextureFormat mTextureFormat;
        ITexture::TextureType mTextureType;


        PackageTexture();
    };

    /* PackageMaterial definition */
    struct PackageMaterial
    {
        std::string mName;
        PackageTexture mDiffuseTexture;
        Vec3 mDiffuseColor;
        Vec3 mAmbientColor;
        Vec3 mSpecularColor;
        Vec3 mEmissiveColor;


        PackageMaterial();
    };

    /* PackageModel definition */
    struct PackageModel
    {
        std::string mName;
        std::vector<PackageModel> mChildren;
        std::vector<PackageMesh> mMeshes;
        Mat4 mTransform;


        PackageModel();
    };

    /* JonsPackage definition */
    struct JonsPackage
    {
        PackageHeader mHeader;
        std::vector<PackageModel> mModels;
        std::vector<PackageMaterial> mMaterials;


        JonsPackage();
    };

我正在使用 Boost Serialization 从文件系统保存/加载，直到现在这一直非常棒，因为它几乎不需要代码来完成。

但是在导入一些 3d 模型然后尝试再次加载它之后，加载时间非常长；从文件系统加载然后反序列化需要将近 30 秒。

这是序列化/反序列化的代码:

JonsPackagePtr ReadJonsPkg(const std::string& jonsPkgName)
    {
        std::ifstream jonsPkgStream(jonsPkgName.c_str(), std::ios::in | std::ios::binary);        // TODO: support opening of older resource packages
        JonsPackagePtr pkg(HeapAllocator::GetDefaultHeapAllocator().AllocateObject<JonsPackage>(), boost::bind(&HeapAllocator::DeallocateObject<JonsPackage>, &HeapAllocator::GetDefaultHeapAllocator(), _1));

        if (jonsPkgStream && jonsPkgStream.good() && jonsPkgStream.is_open())
        {
            std::stringstream buf(std::ios_base::binary | std::ios_base::in | std::ios_base::out);
            buf << jonsPkgStream.rdbuf();
            buf.seekg(0);
            jonsPkgStream.close();

            boost::archive::binary_iarchive iar(buf);

            iar >> (*pkg.get());
        }

        jonsPkgStream.close();

        return pkg;
    }

    bool WriteJonsPkg(const std::string& jonsPkgName, const JonsPackagePtr pkg)
    {
        std::ofstream outStream(jonsPkgName.c_str(), std::ios::out | std::ios::binary | std::ios::trunc);
        bool ret = false;

        if (outStream.is_open())
        {
            boost::archive::binary_oarchive oar(outStream);
            oar << (*pkg.get());

            ret = true;
        }

        return ret;
    }

这是 VS2012 性能分析的图像: http://postimg.org/image/smdsnu5gl/

我正在使用的资源文件在光盘上大约有 26 MB，包含 3 个包模型和 14 个包纹理。我能做些什么，我的文件格式设计是死胡同吗？

Answer 1

对于只有 26MB 的空间来说，时间太多了。我看到你在 VS2012 中运行它。我建议您尝试发布并在 VS2012 环境之外运行该程序，只需直接从文件资源管理器中单击您的 .exe。

此外，您不需要将整个文件加载到内存中来反序列化其内容。

你可以试试下面的代码:

std::ifstream file("path.dat");
boost::archive::binary_iarchive iar(file);