CUDA

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CUDA
Original authorsIan Buck
John Nickolls
DeveloperNvidia
Initial releaseFebruary 16, 2007; 19 years ago (2007-02-16)[1]
Repository
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Written inC
Engine
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    Operating systemWindows, Linux
    PlatformSupported GPUs
    TypeGPGPU
    LicenseProprietary

    CUDA (Compute Unified Device Architecture) is a proprietary[2] parallel computing platform and application programming interface (API) that allows software to use certain types of graphics processing units (GPUs) for accelerated general-purpose processing, significantly broadening their utility in scientific and high-performance computing. CUDA was created by Nvidia starting in 2004 and was officially released in 2007.[3] When it was first introduced, the name was an acronym for Compute Unified Device Architecture,[4] but Nvidia later dropped the common use of the acronym and now rarely expands it.[5]

    CUDA is both a software layer that manages data, giving direct access to the GPU and CPU as necessary, and a library of APIs that enable parallel computation for various needs.[6][7] In addition to drivers and runtime kernels, the CUDA platform includes compilers, libraries and developer tools to help programmers accelerate their applications.

    CUDA is written in the C programming language but is designed to work with a wide array of other programming languages including C++, Fortran, Python and Julia. This accessibility makes it easier for specialists in parallel programming to use GPU resources, in contrast to prior APIs like Direct3D and OpenGL, which require advanced skills in graphics programming.[8] CUDA-powered GPUs also support programming frameworks such as OpenMP, OpenACC and OpenCL.[9][6]

    Background

    [edit | edit source]

    The graphics processing unit (GPU), as a specialized computer processor, addresses the demands of real-time high-resolution 3D graphics compute-intensive tasks. By 2012, GPUs had evolved into highly parallel multi-core systems allowing efficient manipulation of large blocks of data. This design is more effective than general-purpose central processing unit (CPUs) for algorithms in situations where processing large blocks of data is done in parallel, such as:

    The origins of CUDA trace to the early 2000s, when Ian Buck, a computer science Ph.D. student at Stanford University, began experimenting with using GPUs for purposes beyond rendering graphics. Buck had first become interested in GPUs during his undergraduate studies at Princeton University, initially through video gaming. After graduation, he interned at Nvidia, gaining deeper exposure to GPU architecture. At Stanford, he built an 8K gaming rig using 32 GeForce graphics cards, originally to push the limits of graphics performance in games like Quake and Doom. However, his interests shifted toward exploring the potential of GPUs for general-purpose parallel computing.[10]

    To that end, Buck developed Brook, a programming language designed to enable general-purpose computing on GPUs. His work attracted support from both Nvidia and the Defense Advanced Research Projects Agency (DARPA). In 2004, Nvidia hired Buck and paired him with John Nickolls[11], the company's director of architecture for GPU computing. Together, they began transforming Brook into what would become CUDA.[10] CUDA was officially released by Nvidia in 2007.

    Under the leadership of Nvidia CEO Jensen Huang, CUDA became central to the company's strategy of positioning GPUs as versatile hardware for scientific applications. By 2015, CUDA's development increasingly focused on accelerating machine learning and artificial neural network workloads.[12]

    Ontology

    [edit | edit source]

    The following table offers a non-exact description for the ontology of the CUDA framework.

    The ontology of CUDA framework
    memory
    (hardware)
    memory (code, or variable scoping) computation
    (hardware)
    computation
    (code syntax)
    computation
    (code semantics)
    RAM non-CUDA variables host program one routine call
    VRAM,
    GPU L2 cache
    global, const, texture device grid simultaneous call of the same subroutine on many processors
    GPU L1 cache local, shared SM ("streaming multiprocessor") block individual subroutine call
    warp = 32 threads SIMD instructions
    GPU L0 cache,
    register
    thread (aka. "SP", "streaming processor", "cuda core", but these names are now deprecated) analogous to individual scalar ops within a vector op

    Programming abilities

    [edit | edit source]
    File:CUDA processing flow (En).PNG
    Example of CUDA processing flow
    1. Copy data from main memory to GPU memory
    2. CPU initiates the GPU compute kernel
    3. GPU's CUDA cores execute the kernel in parallel
    4. Copy the resulting data from GPU memory to main memory

    The CUDA platform is accessible to software developers through CUDA-accelerated libraries, compiler directives such as OpenACC, and extensions to industry-standard programming languages including C, C++, Fortran and Python. C/C++ programmers can use 'CUDA C/C++', compiled to PTX with nvcc (Nvidia's LLVM-based C/C++ compiler)[13] or by clang itself.[14] Fortran programmers can use 'CUDA Fortran', compiled with the PGI CUDA Fortran compiler from The Portland Group.[needs update] Python programmers can use the cuPyNumeric library to accelerate applications on Nvidia GPUs.

    In addition to libraries, compiler directives, CUDA C/C++ and CUDA Fortran, the CUDA platform supports other computational interfaces, including the Khronos Group's OpenCL,[15] Microsoft's DirectCompute, OpenGL Compute Shader and C++ AMP.[16] Third party wrappers are also available for Python, Perl, Fortran, Java, Ruby, Lua, Common Lisp, Haskell, R, MATLAB, IDL, Julia, and native support in Mathematica.

    In the computer game industry, GPUs are used for graphics rendering, and for game physics calculations (physical effects such as debris, smoke, fire, fluids); examples include PhysX and Bullet. CUDA has also been used to accelerate non-graphical applications in computational biology, cryptography and other fields by an order of magnitude or more.[17][18][19][20][21]

    CUDA provides both a low level API (CUDA Driver API, non single-source) and a higher level API (CUDA Runtime API, single-source). The initial CUDA SDK was made public on 15 February 2007, for Microsoft Windows and Linux. Mac OS X support was later added in version 2.0,[22] which supersedes the beta released February 14, 2008.[23] CUDA works with all Nvidia GPUs from the G8x series onwards, including GeForce, Quadro and the Tesla line. CUDA is compatible with most standard operating systems.

    CUDA 8.0 comes with the following libraries (for compilation & runtime, in alphabetical order):

    • cuBLAS – CUDA Basic Linear Algebra Subroutines library
    • CUDART – CUDA Runtime library
    • cuFFT – CUDA Fast Fourier Transform library
    • cuRAND – CUDA Random Number Generation library
    • cuSOLVER – CUDA based collection of dense and sparse direct solvers
    • cuSPARSE – CUDA Sparse Matrix library
    • NPP – NVIDIA Performance Primitives library
    • nvGRAPH – NVIDIA Graph Analytics library
    • NVML – NVIDIA Management Library
    • NVRTC – NVIDIA Runtime Compilation library for CUDA C++

    CUDA 8.0 comes with these other software components:

    • nView – NVIDIA nView Desktop Management Software
    • NVWMI – NVIDIA Enterprise Management Toolkit
    • GameWorks PhysX – is a multi-platform game physics engine

    CUDA 9.0–9.2 comes with these other components:

    • CUTLASS 1.0 – custom linear algebra algorithms,
    • NVIDIA Video Decoder was deprecated in CUDA 9.2; it is now available in NVIDIA Video Codec SDK

    CUDA 10 comes with these other components:

    • nvJPEG – Hybrid (CPU and GPU) JPEG processing

    CUDA 11.0–11.8 comes with these other components:[24][25][26][27]

    • CUB is new one of more supported C++ libraries
    • MIG multi instance GPU support
    • nvJPEG2000 – JPEG 2000 encoder and decoder

    Advantages

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    CUDA has several advantages over traditional general-purpose computation on GPUs (GPGPU) using graphics APIs:

    • Scattered reads – code can read from arbitrary addresses in memory
    • Unified virtual memory (CUDA 4.0 and above)
    • Unified memory (CUDA 6.0 and above)
    • Shared memory – CUDA exposes a fast shared memory region that can be shared among threads. This can be used as a user-managed cache, enabling higher bandwidth than is possible using texture lookups.[28]
    • Faster downloads and readbacks to and from the GPU
    • Full support for integer and bitwise operations, including integer texture lookups

    Limitations

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    • Whether for the host computer or the GPU device, all CUDA source code is now processed according to C++ syntax rules.[29] This was not always the case. Earlier versions of CUDA were based on C syntax rules.[30] As with the more general case of compiling C code with a C++ compiler, it is therefore possible that old C-style CUDA source code will either fail to compile or will not behave as originally intended.
    • Interoperability with rendering languages such as OpenGL is one-way, with OpenGL having access to registered CUDA memory but CUDA not having access to OpenGL memory.
    • Copying between host and device memory may incur a performance hit due to system bus bandwidth and latency (this can be partly alleviated with asynchronous memory transfers, handled by the GPU's DMA engine).
    • Threads should be running in groups of at least 32 for best performance, with total number of threads numbering in the thousands. Branches in the program code do not affect performance significantly, provided that each of 32 threads takes the same execution path; the SIMD execution model becomes a significant limitation for any inherently divergent task (e.g. traversing a space partitioning data structure during ray tracing).
    • No emulation or fallback functionality is available for modern revisions.
    • Valid C++ may sometimes be flagged and prevent compilation due to the way the compiler approaches optimization for target GPU device limitations.[citation needed]
    • C++ run-time type information (RTTI) and C++-style exception handling are only supported in host code, not in device code.
    • In single-precision on first generation CUDA compute capability 1.x devices, denormal numbers are unsupported and are instead flushed to zero, and the precision of both the division and square root operations are slightly lower than IEEE 754-compliant single precision math. Devices that support compute capability 2.0 and above support denormal numbers, and the division and square root operations are IEEE 754 compliant by default. However, users can obtain the prior faster gaming-grade math of compute capability 1.x devices if desired by setting compiler flags to disable accurate divisions and accurate square roots, and enable flushing denormal numbers to zero.[31]
    • Unlike OpenCL, CUDA-enabled GPUs are only available from Nvidia as it is proprietary.[32][2] Attempts to implement CUDA on other GPUs include:
      • Project Coriander: Converts CUDA C++11 source to OpenCL 1.2 C. A fork of CUDA-on-CL intended to run TensorFlow.[33][34][35]
      • CU2CL: Convert CUDA 3.2 C++ to OpenCL C.[36]
      • GPUOpen HIP: A thin abstraction layer on top of CUDA and ROCm intended for AMD and Nvidia GPUs. Has a conversion tool for importing CUDA C++ source. Supports CUDA 4.0 plus C++11 and float16.
      • ZLUDA is a drop-in replacement for CUDA on AMD GPUs and formerly Intel GPUs with near-native performance.[37] The developer, Andrzej Janik, was separately contracted by both Intel and AMD to develop the software in 2021 and 2022, respectively. However, neither company decided to release it officially due to the lack of a business use case. AMD's contract included a clause that allowed Janik to release his code for AMD independently, allowing him to release the new version that only supports AMD GPUs.[38]
      • ChipStar can compile and run CUDA/HIP programs on advanced OpenCL 3.0 or Level Zero platforms.[39]
      • SCALE is a CUDA-compatible programming toolkit for ahead of time compilation of CUDA source code on AMD GPUs, aiming to expand support for other GPUs in the future.[40]

    Example

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    This example code in C++ loads a texture from an image into an array on the GPU:

    texture<float, 2, cudaReadModeElementType> tex;
    
    void foo() {
        cudaArray* cu_array;
    
        // Allocate array
        cudaChannelFormatDesc description = cudaCreateChannelDesc<float>();
        cudaMallocArray(&cu_array, &description, width, height);
    
        // Copy image data to array
        cudaMemcpyToArray(cu_array, image, width*height*sizeof(float), cudaMemcpyHostToDevice);
    
        // Set texture parameters (default)
        tex.addressMode[0] = cudaAddressModeClamp;
        tex.addressMode[1] = cudaAddressModeClamp;
        tex.filterMode = cudaFilterModePoint;
        tex.normalized = false; // do not normalize coordinates
    
        // Bind the array to the texture
        cudaBindTextureToArray(tex, cu_array);
    
        // Run kernel
        dim3 blockDim(16, 16, 1);
        dim3 gridDim((width + blockDim.x - 1)/ blockDim.x, (height + blockDim.y - 1) / blockDim.y, 1);
        kernel<<< gridDim, blockDim, 0 >>>(d_data, height, width);
    
        // Unbind the array from the texture
        cudaUnbindTexture(tex);
    }
    
    __global__ void kernel(float* odata, int height, int width) {
        unsigned int x = blockIdx.x*blockDim.x + threadIdx.x;
        unsigned int y = blockIdx.y*blockDim.y + threadIdx.y;
        if (x < width && y < height) {
            float c = tex2D(tex, x, y);
            odata[y*width+x] = c;
        }
    }
    

    Below is an example given in Python that computes the product of two arrays on the GPU. The unofficial Python language bindings can be obtained from PyCUDA.[41]

    import numpy
    import pycuda.autoinit
    
    from numpy.typing import NDArray, float32
    from pycuda.compiler import SourceModule
    from pycuda.driver import Function, In, Out
    
    mod: SourceModule = SourceModule(
        """
    __global__ void multiply_them(float* dest, float* a, float* b) {
        const int i = threadIdx.x;
        dest[i] = a[i] * b[i];
    }
    """
    )
    
    multiply_them: Function = mod.get_function("multiply_them")
    
    a: NDArray[float32] = numpy.random.randn(400).astype(numpy.float32)
    b: NDArray[float32] = numpy.random.randn(400).astype(numpy.float32)
    
    dest: NDArray[float32] = numpy.zeros_like(a)
    multiply_them(Out(dest), In(a), In(b), block=(400, 1, 1))
    
    print(dest - a * b)
    

    Additional Python bindings to simplify matrix multiplication operations can be found in the program pycublas.[42]

     
    import numpy
    
    from pycublas import CUBLASMatrix
    
    A: CUBLASMatrix = CUBLASMatrix(numpy.mat([[1, 2, 3], [4, 5, 6]], numpy.float32))
    B: CUBLASMatrix = CUBLASMatrix(numpy.mat([[2, 3], [4, 5], [6, 7]], numpy.float32))
    C: CUBLASMatrix = A * B
    print(C.np_mat())
    

    while CuPy directly replaces NumPy:[43]

    import cupy
    
    from cupy.typing import NDArray, float64
    
    a: NDArray[float64] = cupy.random.randn(400)
    b: NDArray[float64] = cupy.random.randn(400)
    
    dest: NDArray[float64] = cupy.zeros_like(a)
    
    print(dest - a * b)
    

    GPUs supported

    [edit | edit source]

    Note on notation: compute capacity X.Y is also written SMXY or sm_XY (e.g. 10.3 as SM103 or sm_103) in professional Nvidia software and the code Nvidia has contributed to LLVM.[44]

    Below is a table of supported CUDA compute capabilities based on the CUDA SDK version and microarchitecture, listed by code name:

    Note: CUDA SDK 10.2 is the last official release for macOS, as support will not be available for macOS in newer releases.

    CUDA compute capability by version with associated GPU semiconductors and GPU card models (separated by their various application areas):

    * – OEM-only products

    1. ^ CUDA Toolkit 13.0 renamed the SM101 for Thor GPUs to SM110.

    Version features and specifications

    [edit | edit source]

    Note: A GPU with a higher compute capacity is able to execute PTX code meant for a GPU of a lower range of compute capacities. However, it is possible to compile CUDA code into a form that only works on one family (same "X") of GPUs; if existing code is compiled this way, recompilation will be needed for it to work on a newer GPU.[44]

    Feature support (unlisted features are supported for all compute capabilities) Compute capability (version)
    1.0, 1.1 1.2, 1.3 2.x 3.0 3.2 3.5, 3.7, 5.x, 6.x, 7.0, 7.2 7.5 8.x 9.0, 10.x, 12.x
    Warp vote functions (__all(), __any()) No Yes
    Warp vote functions (__ballot()) No Yes
    Memory fence functions (__threadfence_system())
    Synchronization functions (__syncthreads_count(), __syncthreads_and(), __syncthreads_or())
    Surface functions
    3D grid of thread blocks
    Warp shuffle functions No Yes
    Unified memory programming
    Funnel shift No Yes
    Dynamic parallelism No Yes
    Uniform Datapath[64] No Yes
    Hardware-accelerated async-copy No Yes
    Hardware-accelerated split arrive/wait barrier
    Warp-level support for reduction ops
    L2 cache residency management
    DPX instructions for accelerated dynamic programming No Yes
    Distributed shared memory
    Thread block cluster
    Tensor memory accelerator (TMA) unit
    Feature support (unlisted features are supported for all compute capabilities) 1.0, 1.1 1.2, 1.3 2.x 3.0 3.2 3.5, 3.7, 5.x, 6.x, 7.0, 7.2 7.5 8.x 9.0, 10.x, 12.x
    Compute capability (version)

    [65]

    Data types

    [edit | edit source]

    Floating-point types

    [edit | edit source]
    Data type Supported vector types Storage Length Bits
    (complete vector)
    Used Length Bits
    (single value)
    Sign Bits Exponent Bits Mantissa Bits Comments
    E2M1 = FP4 e2m1x2 / e2m1x4 8 / 16 4 1 2 1
    E2M3 = FP6 variant e2m3x2 / e2m3x4 16 / 32 6 1 2 3
    E3M2 = FP6 variant e3m2x2 / e3m2x4 16 / 32 6 1 3 2
    UE4M3 ue4m3 8 7 0 4 3 Used for scaling (E2M1 only)
    E4M3 = FP8 variant e4m3 / e4m3x2 / e4m3x4 8 / 16 / 32 8 1 4 3
    E5M2 = FP8 variant e5m2 / e5m2x2 / e5m2x4 8 / 16 / 32 8 1 5 2 Exponent/range of FP16, fits into 8 bits
    UE8M0 ue8m0x2 16 8 0 8 0 Used for scaling (any FP4 or FP6 or FP8 format)
    FP16 f16 / f16x2 16 / 32 16 1 5 10
    BF16 bf16 / bf16x2 16 / 32 16 1 8 7 Exponent/range of FP32, fits into 16 bits
    TF32 tf32 32 19 1 8 10 Exponent/range of FP32, mantissa/precision of FP16
    FP32 f32 / f32x2 32 / 64 32 1 8 23
    FP64 f64 64 64 1 11 52

    Version support

    [edit | edit source]
    Data type Basic Operations Supported since
    Atomic Operations Supported since
    for global memory
    Supported since
    for shared memory
    8-bit integer
    signed/unsigned
    loading, storing, conversion 1.0
    16-bit integer
    signed/unsigned
    general operations 1.0 atomicCAS() 3.5
    32-bit integer
    signed/unsigned
    general operations 1.0 atomic functions 1.1 1.2
    64-bit integer
    signed/unsigned
    general operations 1.0 atomic functions 1.2 2.0
    any 128-bit trivially copyable type general operations No atomicExch, atomicCAS 9.0
    16-bit floating point
    FP16
    addition, subtraction,
    multiplication, comparison,
    warp shuffle functions, conversion
    5.3 half2 atomic addition 6.0
    atomic addition 7.0
    16-bit floating point
    BF16
    addition, subtraction,
    multiplication, comparison,
    warp shuffle functions, conversion
    8.0 atomic addition 8.0
    32-bit floating point general operations 1.0 atomicExch() 1.1 1.2
    atomic addition 2.0
    32-bit floating point float2 and float4 general operations No atomic addition 9.0
    64-bit floating point general operations 1.3 atomic addition 6.0

    Note: Any missing lines or empty entries do reflect some lack of information on that exact item.[66]

    Tensor cores

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    FMA per cycle per tensor core[67] Supported since 7.0 7.2 7.5 Workstation 7.5 Desktop 8.0 8.6 Workstation 8.7 8.6 Desktop 8.9 Desktop 8.9 Workstation 9.0 10.0 10.1 12.0
    Data Type For dense matrices For sparse matrices 1st Gen (8x/SM) 1st Gen? (8x/SM) 2nd Gen (8x/SM) 3rd Gen (4x/SM) 4th Gen (4x/SM) 5th Gen (4x/SM)
    1-bit values (AND) 8.0 as
    experimental
    No No 4096 2048 speed tbd
    1-bit values (XOR) 7.5–8.9 as
    experimental
    No 1024 Deprecated or removed?
    4-bit integers 8.0–8.9 as
    experimental
    256 1024 512
    4-bit floating point FP4 (E2M1) 10.0 No 4096 tbd 512
    6-bit floating point FP6 (E3M2 and E2M3) 10.0 No 2048 tbd
    8-bit integers 7.2 8.0 No 128 128 512 256 1024 2048 256
    8-bit floating point FP8 (E4M3 and E5M2) with FP16 accumulate 8.9 No 256
    8-bit floating point FP8 (E4M3 and E5M2) with FP32 accumulate 128 128
    16-bit floating point FP16 with FP16 accumulate 7.0 8.0 64 64 64 256 128 512 1024 128
    16-bit floating point FP16 with FP32 accumulate 32 64 128 64
    16-bit floating point BF16 with FP32 accumulate 7.5[68] 8.0 No 64[69]
    32-bit (19 bits used) floating point TF32 speed tbd (32?)[69] 128 32 64 256 512 32
    64-bit floating point 8.0 No No 16 speed tbd 32 16 tbd

    Note: Any missing lines or empty entries do reflect some lack of information on that exact item.[70][71][72][73][74][75]

    Tensor Core Composition 7.0 7.2, 7.5 8.0, 8.6 8.7 8.9 9.0
    Dot Product Unit Width in FP16 units (in bytes)[76][77][78][79] 4 (8) 8 (16) 4 (8) 16 (32)
    Dot Product Units per Tensor Core 16 32
    Tensor Cores per SM partition 2 1
    Full throughput (Bytes/cycle)[80] per SM partition[81] 256 512 256 1024
    FP Tensor Cores: Minimum cycles for warp-wide matrix calculation 8 4 8
    FP Tensor Cores: Minimum Matrix Shape for full throughput (Bytes)[82] 2048
    INT Tensor Cores: Minimum cycles for warp-wide matrix calculation No 4
    INT Tensor Cores: Minimum Matrix Shape for full throughput (Bytes) No 1024 2048 1024

    [83][84][85][86]

    FP64 Tensor Core Composition 8.0 8.6 8.7 8.9 9.0
    Dot Product Unit Width in FP64 units (in bytes) 4 (32) tbd 4 (32)
    Dot Product Units per Tensor Core 4 tbd 8
    Tensor Cores per SM partition 1
    Full throughput (Bytes/cycle)[80] per SM partition[81] 128 tbd 256
    Minimum cycles for warp-wide matrix calculation 16 tbd
    Minimum Matrix Shape for full throughput (Bytes)[82] 2048

    Technical specifications

    [edit | edit source]
    Technical specifications Compute capability (version)
    1.0 1.1 1.2 1.3 2.x 3.0 3.2 3.5 3.7 5.0 5.2 5.3 6.0 6.1 6.2 7.0 7.2 7.5 8.0 8.6 8.7 8.9 9.0 10.x 12.x
    Maximum number of resident grids per device
    (concurrent kernel execution, can be lower for specific devices)
    1 16 4 32 16 128 32 16 128 16 128
    Maximum dimensionality of grid of thread blocks 2 3
    Maximum x-dimension of a grid of thread blocks 65535 231 − 1
    Maximum y-, or z-dimension of a grid of thread blocks 65535
    Maximum dimensionality of thread block 3
    Maximum x- or y-dimension of a block 512 1024
    Maximum z-dimension of a block 64
    Maximum number of threads per block 512 1024
    Warp size 32
    Maximum number of resident blocks per multiprocessor 8 16 32 16 32 16 24 32
    Maximum number of resident warps per multiprocessor 24 32 48 64 32 64 48 64 48
    Maximum number of resident threads per multiprocessor 768 1024 1536 2048 1024 2048 1536 2048 1536
    Number of 32-bit regular registers per multiprocessor 8 K 16 K 32 K 64 K 128 K 64 K
    Number of 32-bit uniform registers per multiprocessor No 2 K[87]

    [88]

    Maximum number of 32-bit registers per thread block 8 K 16 K 32 K 64 K 32 K 64 K 32 K 64 K 32 K 64 K
    Maximum number of 32-bit regular registers per thread 124 63 255
    Maximum number of 32-bit uniform registers per warp No 63[87]

    [89]

    Amount of shared memory per multiprocessor
    (out of overall shared memory + L1 cache, where applicable)
    16 KiB 16 / 48 KiB (of 64 KiB) 16 / 32 / 48 KiB (of 64 KiB) 80 / 96 / 112 KiB (of 128 KiB) 64 KiB 96 KiB 64 KiB 96 KiB 64 KiB 0 / 8 / 16 / 32 / 64 / 96 KiB (of 128 KiB) 32 / 64 KiB (of 96 KiB) 0 / 8 / 16 / 32 / 64 / 100 / 132 / 164 KiB (of 192 KiB) 0 / 8 / 16 / 32 / 64 / 100 KiB (of 128 KiB) 0 / 8 / 16 / 32 / 64 / 100 / 132 / 164 KiB (of 192 KiB) 0 / 8 / 16 / 32 / 64 / 100 KiB (of 128 KiB) 0 / 8 / 16 / 32 / 64 / 100 / 132 / 164 / 196 / 228 KiB (of 256 KiB) 0 / 8 / 16 / 32 / 64 / 100 KiB (of 128 KiB)
    Maximum amount of shared memory per thread block 16 KiB 48 KiB 96 KiB 48 KiB 64 KiB 163 KiB 99 KiB 163 KiB 99 KiB 227 KiB 99 KiB
    Number of shared memory banks 16 32
    Amount of local memory per thread 16 KiB 512 KiB
    Constant memory size accessible by CUDA C/C++
    (1 bank, PTX can access 11 banks, SASS can access 18 banks)
    64 KiB
    Cache working set per multiprocessor for constant memory 8 KiB 4 KiB 8 KiB
    Cache working set per multiprocessor for texture memory 16 KiB per TPC 24 KiB per TPC 12 KiB 12 – 48 KiB[90] 24 KiB 48 KiB 32 KiB[91] 24 KiB 48 KiB 24 KiB 32 – 128 KiB 32 – 64 KiB 28 – 192 KiB 28 – 128 KiB 28 – 192 KiB 28 – 128 KiB 28 – 256 KiB
    Maximum width for 1D texture reference bound to a CUDA
    array
    8192 65536 131072
    Maximum width for 1D texture reference bound to linear
    memory
    227 228 227 228 227 228
    Maximum width and number of layers for a 1D layered
    texture reference
    8192 × 512 16384 × 2048 32768 x 2048
    Maximum width and height for 2D texture reference bound
    to a CUDA array
    65536 × 32768 65536 × 65535 131072 x 65536
    Maximum width and height for 2D texture reference bound
    to a linear memory
    65000 x 65000 65536 x 65536 131072 x 65000
    Maximum width and height for 2D texture reference bound
    to a CUDA array supporting texture gather
    16384 x 16384 32768 x 32768
    Maximum width, height, and number of layers for a 2D
    layered texture reference
    8192 × 8192 × 512 16384 × 16384 × 2048 32768 x 32768 x 2048
    Maximum width, height and depth for a 3D texture
    reference bound to linear memory or a CUDA array
    20483 40963 163843
    Maximum width (and height) for a cubemap texture reference 16384 32768
    Maximum width (and height) and number of layers
    for a cubemap layered texture reference
    16384 × 2046 32768 × 2046
    Maximum number of textures that can be bound to a
    kernel
    128 256
    Maximum width for a 1D surface reference bound to a
    CUDA array
    Not
    supported
    65536 16384 32768
    Maximum width and number of layers for a 1D layered
    surface reference
    65536 × 2048 16384 × 2048 32768 × 2048
    Maximum width and height for a 2D surface reference
    bound to a CUDA array
    65536 × 32768 16384 × 65536 131072 × 65536
    Maximum width, height, and number of layers for a 2D
    layered surface reference
    65536 × 32768 × 2048 16384 × 16384 × 2048 32768 × 32768 × 2048
    Maximum width, height, and depth for a 3D surface
    reference bound to a CUDA array
    65536 × 32768 × 2048 4096 × 4096 × 4096 16384 × 16384 × 16384
    Maximum width (and height) for a cubemap surface reference bound to a CUDA array 32768 16384 32768
    Maximum width and number of layers for a cubemap
    layered surface reference
    32768 × 2046 16384 × 2046 32768 × 2046
    Maximum number of surfaces that can be bound to a
    kernel
    8 16 32
    Maximum number of instructions per kernel 2 million 512 million
    Maximum number of Thread Blocks per Thread Block Cluster[92] No 16 8
    Technical specifications 1.0 1.1 1.2 1.3 2.x 3.0 3.2 3.5 3.7 5.0 5.2 5.3 6.0 6.1 6.2 7.0 7.2 7.5 8.0 8.6 8.7 8.9 9.0 10.x 12.x
    Compute capability (version)
    [93][94]

    Multiprocessor architecture

    [edit | edit source]
    Architecture specifications Compute capability (version)
    1.0 1.1 1.2 1.3 2.0 2.1 3.0 3.2 3.5 3.7 5.0 5.2 5.3 6.0 6.1 6.2 7.0 7.2 7.5 8.0 8.6 8.7 8.9 9.0 10.x 12.x
    Number of ALU lanes for INT32 arithmetic operations 8 32 48 192[95] 128 128 64 128 128 64 64 64 128
    Number of ALU lanes for any INT32 or FP32 arithmetic operation
    Number of ALU lanes for FP32 arithmetic operations 64 64 128 128
    Number of ALU lanes for FP16x2 arithmetic operations No 1 128[96] 128[97] 64[98]
    Number of ALU lanes for FP64 arithmetic operations No 1 16 by FP32[99] 4 by FP32[100] 8 8 / 64[101] 64 4[102] 32 4 32 2 32 2 64 2
    Number of Load/Store Units 4 per 2 SM 8 per 2 SM 8 per 2 SM / 3 SM[101] 8 per 3 SM 16 32 16 32 16 32
    Number of special function units for single-precision floating-point transcendental functions 2[103] 4 8 32 16 32 16
    Number of texture mapping units (TMU) 4 per 2 SM 8 per 2 SM 8 per 2 / 3SM[101] 8 per 3 SM 4 4 / 8[101] 16 8 16 8 4
    Number of ALU lanes for uniform INT32 arithmetic operations No 2[104]
    Number of tensor cores No 8 (1st gen.)[105] 0 / 8[101] (2nd gen.) 4 (3rd gen.) 4 (4th gen.)
    Number of raytracing cores No 0 / 1[101] (1st gen.) No 1 (2nd gen.) No 1 (3rd gen.) No
    Number of SM Partitions = Processing Blocks[106] 1 4 2 4
    Number of warp schedulers per SM partition 1 2 4 1
    Max number of new instructions issued each cycle by a single scheduler[107] 2[108] 1 2[109] 2 1
    Size of unified memory for data cache and shared memory 16 KiB[110] 16 KiB[110] 64 KiB 128 KiB 64 KiB SM + 24 KiB L1 (separate)[111] 96 KiB SM + 24 KiB L1 (separate)[111] 64 KiB SM + 24 KiB L1 (separate)[111] 64 KiB SM + 24 KiB L1 (separate)[111] 96 KiB SM + 24 KiB L1 (separate)[111] 64 KiB SM + 24 KiB L1 (separate)[111] 128 KiB 96 KiB[112] 192 KiB 128 KiB 192 KiB 128 KiB 256 KiB
    Size of L3 instruction cache per GPU 32 KiB[113] use L2 Data Cache
    Size of L2 instruction cache per Texture Processor Cluster (TPC) 8 KiB
    Size of L1.5 instruction cache per SM[114] 4 KiB 32 KiB 32 KiB 48 KiB[91] 128 KiB 32 KiB 128 KiB ~46 KiB[115] 128 KiB[116]
    Size of L1 instruction cache per SM 8 KiB 8 KiB
    Size of L0 instruction cache per SM partition only 1 partition per SM No 12 KiB 16 KiB?[117] 32 KiB
    Instruction Width[114] 32 bits instructions and 64 bits instructions[118] 64 bits instructions + 64 bits control logic every 7 instructions 64 bits instructions + 64 bits control logic every 3 instructions 128 bits combined instruction and control logic
    Memory Bus Width per Memory Partition in bits 64 ((G)DDR) 32 ((G)DDR) 512 (HBM) 32 ((G)DDR) 512 (HBM) 32 ((G)DDR) 512 (HBM) 32 ((G)DDR) 512 (HBM) 32 ((G)DDR)
    L2 Cache per Memory Partition 16 KiB[119] 32 KiB[119] 128 KiB 256 KiB 1 MiB 512 KiB 128 KiB 512 KiB 256 KiB 128 KiB 768 KiB 64 KiB 512 KiB 4 MiB 512 KiB 8 MiB[120] 5 MiB 6.25 MiB 8 MiB[121]
    Number of Render Output Units (ROP) per memory partition (or per GPC in later models) 4 8 4 8 16 8 12 8 4 16 2 8 16 16 per GPC 3 per GPC 16 per GPC
    Architecture specifications 1.0 1.1 1.2 1.3 2.0 2.1 3.0 3.2 3.5 3.7 5.0 5.2 5.3 6.0 6.1 6.2 7.0 7.2 7.5 8.0 8.6 8.7 8.9 9.0 10.x 12.x
    Compute capability (version)

    For more information read the Nvidia CUDA C++ Programming Guide.[122]

    Usages of CUDA architecture

    [edit | edit source]

    Comparison with competitors

    [edit | edit source]

    CUDA competes with other GPU computing stacks: Intel OneAPI and AMD ROCm.

    Whereas Nvidia's CUDA is closed-source, Intel's OneAPI and AMD's ROCm are open source.

    Intel OneAPI

    [edit | edit source]

    oneAPI is an initiative based in open standards, created to support software development for multiple hardware architectures.[125] The oneAPI libraries must implement open specifications that are discussed publicly by the Special Interest Groups, offering the possibility for any developer or organization to implement their own versions of oneAPI libraries.[126][127]

    Originally made by Intel, other hardware adopters include Fujitsu and Huawei.

    Unified Acceleration Foundation (UXL)

    [edit | edit source]

    Unified Acceleration Foundation (UXL) is a new technology consortium working on the continuation of the OneAPI initiative, with the goal to create a new open standard accelerator software ecosystem, related open standards and specification projects through Working Groups and Special Interest Groups (SIGs). The goal is to offer open alternatives to Nvidia's CUDA. The main companies behind it are Intel, Google, ARM, Qualcomm, Samsung, Imagination, and VMware.[128]

    AMD ROCm

    [edit | edit source]

    ROCm[129] is an open source software stack for graphics processing unit (GPU) programming from Advanced Micro Devices (AMD).

    See also

    [edit | edit source]

    References

    [edit | edit source]
    1. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    2. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    3. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    4. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    5. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    6. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    7. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    8. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    9. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    10. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    11. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    12. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    13. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    14. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    15. ^ First OpenCL demo on a GPU on YouTube
    16. ^ DirectCompute Ocean Demo Running on Nvidia CUDA-enabled GPU on YouTube
    17. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    18. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    19. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    20. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    21. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    22. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    23. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    24. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    25. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    26. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    27. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    28. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    29. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    30. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    31. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    32. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    33. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    34. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    35. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    36. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    37. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    38. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    39. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    40. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    41. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    42. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    43. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    44. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    45. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    46. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    47. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    48. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    49. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    50. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    51. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    52. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    53. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    54. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    55. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    56. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    57. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    58. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    59. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    60. ^ Nvidia Xavier Specs on TechPowerUp (preliminary)
    61. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    62. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    63. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    64. ^ Dissecting the Turing GPU Architecture through Microbenchmarking
    65. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    66. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    67. ^ Fused-Multiply-Add, actually executed, Dense Matrix
    68. ^ as SASS since 7.5, as PTX since 8.0
    69. ^ a b unofficial support in SASS
    70. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    71. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    72. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    73. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
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    75. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    76. ^ In the Whitepapers the Tensor Core cube diagrams represent the Dot Product Unit Width into the height (4 FP16 for Volta and Turing, 8 FP16 for A100, 4 FP16 for GA102, 16 FP16 for GH100). The other two dimensions represent the number of Dot Product Units (4x4 = 16 for Volta and Turing, 8x4 = 32 for Ampere and Hopper). The resulting gray blocks are the FP16 FMA operations per cycle. Pascal without Tensor core is only shown for speed comparison as is Volta V100 with non-FP16 datatypes.
    77. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
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    79. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    80. ^ a b shape x converted operand size, e.g. 2 tensor cores x 4x4x4xFP16/cycle = 256 Bytes/cycle
    81. ^ a b = product first 3 table rows
    82. ^ a b = product of previous 2 table rows; shape: e.g. 8x8x4xFP16 = 512 Bytes
    83. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
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    87. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
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    89. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    90. ^ dependent on device
    91. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    92. ^ NVIDIA H100 Tensor Core GPU Architecture
    93. ^ H.1. Features and Technical Specifications – Table 14. Technical Specifications per Compute Capability
    94. ^ NVIDIA Hopper Architecture In-Depth
    95. ^ can only execute 160 integer instructions according to programming guide
    96. ^ 128 according to [1]. 64 from FP32 + 64 separate units?
    97. ^ 64 by FP32 cores and 64 by flexible FP32/INT cores.
    98. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    99. ^ 32 FP32 lanes combine to 16 FP64 lanes. Maybe lower depending on model.
    100. ^ only supported by 16 FP32 lanes, they combine to 4 FP64 lanes
    101. ^ a b c d e f depending on model
    102. ^ Effective speed, probably over FP32 ports. No description of actual FP64 cores.
    103. ^ Can also be used for integer additions and comparisons
    104. ^ 2 clock cycles/instruction for each SM partition Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    105. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    106. ^ The schedulers and dispatchers have dedicated execution units unlike with Fermi and Kepler.
    107. ^ Dispatching can overlap concurrently, if it takes more than one cycle (when there are less execution units than 32/SM Partition)
    108. ^ Can dual issue MAD pipe and SFU pipe
    109. ^ No more than one scheduler can issue 2 instructions at once. The first scheduler is in charge of warps with odd IDs. The second scheduler is in charge of warps with even IDs.
    110. ^ a b shared memory only, no data cache
    111. ^ a b c d e f shared memory separate, but L1 includes texture cache
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    117. ^ Note that Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). disagrees and states 2 KiB L0 instruction cache per SM partition and 16 KiB L1 instruction cache per SM
    118. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    119. ^ a b for access with texture engine only
    120. ^ 25% disabled on RTX 4060, RTX 4070, RTX 4070 Ti and RTX 4090
    121. ^ 25% disabled on RTX 5070 Ti and RTX 5090
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    128. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    129. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).

    Further reading

    [edit | edit source]
    • Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    • Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
    [edit | edit source]
    • Lua error in Module:Official_website at line 94: attempt to index field 'wikibase' (a nil value).

    Lua error in Module:Authority_control at line 153: attempt to index field 'wikibase' (a nil value).