The NVIDIA CUDA Profiling Tools Interface (CUPTI) is a dynamic library that enables the creation of profiling and tracing tools that target CUDA applications. CUPTI provides a set of APIs targeted at ISVs creating profilers and other performance optimization tools:

  • the Activity API,
  • the Callback API,
  • the Event API,
  • the Metric API,
  • the Profiler API,
  • the PC Sampling API,
  • the SASS Metric API, and
  • the Checkpoint API

Using these CUPTI APIs, independent software developers can create profiling tools that provide low and deterministic profiling overhead on the target system, while giving insight into the CPU and GPU behavior of CUDA applications. Normally packaged with the CUDA Toolkit, NVIDIA occasionally uses this page to provide CUPTI improvements and bug fixes between toolkit releases.



There is currently no CUPTI update to the CUDA Toolkit 12.4 Update 1. You may obtain the latest version of CUPTI by Downloading the CUDA Toolkit 12.4.1

Download the CUDA Toolkit 12.4 Update 1 Now Download the CUDA Toolkit 12.4 Now
Revision History

Key Features

  • Trace CUDA API by registering callbacks for API calls of interest
    • Full support for entry and exit points in the CUDA C Runtime (CUDART) and CUDA Driver
  • GPU workload trace for the activities happening on the GPU, which includes kernel executions, memory operations (e.g., Host-to-Device memory copies) and memset operations.
  • CUDA Unified Memory trace for transfers from host to device, device to host, device to device and page faults on CPU and GPU etc.
  • Normalized timestamps for CPU and GPU trace
  • Profile hardware and software event counters, including:
    • Utilization metrics for various hardware units
    • Instruction count and throughput
    • Memory load/store events and throughput
    • Cache hits/misses
    • Branches and divergent branches
    • Many more
  • Enables automated bottleneck identification based on metrics such as instruction throughput, memory throughput, and more
  • Range profiling to enable metric collection over concurrent kernel launches within a range
  • Metrics attribution at the high-level source code and the executed assembly instructions.
  • Device-wide sampling of the program counter (PC). The PC Sampling gives the number of samples for each source and assembly line with various stall reasons.
See the CUPTI User Guide for a complete listing of hardware and software event counters available for performance analysis tools.

Updates in CUDA Toolkit 12.4 Update 1

    Resolved Issues
    • Fixed a crash when API cuptiFinalize is used for applications using CUDA Graph.
    • Fixed a crash which can occur while tracing memcpy and memset nodes in a graph when using graph level tracing..
    • Skip delivering worker thread buffers on internal flush if the worker thread buffer is not full.

Updates in CUDA Toolkit 12.4

    New Features
    • Added tracing support for applications using Green contexts. Added two new fields isGreenContext and parentContextId in the context activity record. The activity record CUpti_ActivityContext is deprecated and it is replaced by a new activity record CUpti_ActivityContext2.
    • CUDA API calls are completed asynchronously from the perspective of the host CPU. This is accomplished by queuing the work slated for the GPU into a structure known as a command buffer. If there is insufficient space available in the command buffer when attempting to call a CUDA API, the host call will block until space becomes available. The user should be able to identify when this situation occurs. This is indicated using the new attribute CUPTI_ACTIVITY_OVERHEAD_COMMAND_BUFFER_FULL added in the activity overhead enum CUpti_ActivityOverheadKind. To provide additional details about the overhead, a new field overheadData is added in the overhead activity record. Activity record CUpti_ActivityOverhead2 is deprecated and it is replaced by the new activity record CUpti_ActivityOverhead3.
    • Added process ID and thread ID in the JIT activity record. To accomodate this change, activity record CUpti_ActivityJit is deprecated and it is replaced by a new activity record CUpti_ActivityJit2.
    • To correlate the sampling data for a kernel with the launch API in the serial mode of the PC Sampling APIs, a new field correlationId is added in the struct CUpti_PCSamplingPCData.
    • For PC Sampling APIs, total (smsp__pcsamp_sample_count) and dropped (smsp__pcsamp_samples_data_dropped) sample counts are collected by default.
    Resolved Issues
    • Fixed the issue for overhead records showing the default thread ID than the one requested using the API cuptiSetThreadIdType().
    • Fixed instruction level SASS metrics profiling for CUDA Graph applications.
    • When a device graph is first launched from the device and it is not launched from the host earlier, end timestamp could be 0 for graph-level tracing on Ampere and later GPU architectures. This issue is fixed.

Requirements

    Supported platforms
    • Linux x86_64[1]
    • Windows x86_64[1]
    • Linux aarch64 SBSA[1]
    • DRIVE OS QNX aarch64[2]
    • DRIVE OS Linux aarch64[2]
    [1] available in the CUDA Desktop Toolkit only
    [2] available in the Embedded or Drive toolkits only
    Supported NVIDIA GPU architectures
    • Activity and Callback APIs
      • All architectures supported by CUDA Toolkit
    • Event and Metric APIs
      • Volta
      • Pascal
      • Maxwell
    • Profiling and PC Sampling APIs
      • Hopper: GH100
      • Ada: AD10x
      • Ampere: A100 with Multi-Instance GPU, GA10x
      • Turing
      • Volta: GV100, GV10B
    CUDA Toolkit
    Drivers
      Please use the following drivers
      • 551.78 (Windows)
      • 550.54.15 (Linux)
      provided with CUDA Toolkit 12.4 Update 1 production release or a more recent version.

Documentation

Support

To provide feedback, request additional features, or report issues, please use the Developer Forums.

Installation Overview

When installing CUDA Toolkit 12.4 Update 1 and specifying options, be sure to select CUDA > Development > Tools > CUPTI.