NVIDIA CUDA Profiling Tools Interface (CUPTI) - CUDA Toolkit
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, and
- the Profiler 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.
- 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.
- CUPTI has made the following changes as part of the CUDA Toolkit 11.5 release:
- A new API
cuptiProfilerDeviceSupportedis introduced to expose overall Profiling API support and specific requirements for a given device. Profiling API must be initialized by calling
cuptiProfilerInitializebefore testing device support.
- PC Sampling struct
CUpti_PCSamplingDataintroduces a new field
nonUsrKernelsTotalSamplesto provide information about the number of samples collected for all non-user kernels.
- Activity record
CUpti_ActivityDevice2for device information has been deprecated and replaced by a new activity record
CUpti_ActivityDevice3. New record adds a flag
isCudaVisibleto indicate whether device is visible to CUDA.
- Activity record
CUpti_ActivityNvLink3for NVLINK information has been deprecated and replaced by a new activity record
CUpti_ActivityNvLink4. New record can accommodate NVLINK port information upto a maximum of 32 ports.
- A new CUPTI Checkpoint API is introduced, enabling automatic saving and restoring of device state, and facilitating development of kernel replay tools. This is helpful for User Replay mode of the CUPTI Profiler API, but is not limited to use with CUPTI.
- Tracing is supported on the Windows Subsystem for Linux version 2 (WSL2).
- CUPTI is not supported on NVIDIA Crypto Mining Processors (CMP). A new error code
CUPTI_ERROR_CMP_DEVICE_NOT_SUPPORTEDis introduced to indicate it.
- Linux x86_64
- Windows x86_64
- Linux PowerPC
- Linux aarch64 SBSA
- DRIVE OS QNX aarch64
- DRIVE OS Linux aarch64
- Android aarch64
 available in the Embedded or Drive toolkits only
 does not support Profiling API data collection
Supported NVIDIA GPU architectures
- Activity and Callback APIs
- All architectures supported by CUDA Toolkit
- Event and Metric APIs
- Profiling APIs
- Ampere: A100 with Multi-Instance GPU, GA10x
- Volta: GV100, GV10B
- CUPTI can be found in the CUDA Toolkit 11.5 production release
- Please use the following drivers
- 496.13 (Windows)
- 495.29.05 (Linux)
To provide feedback, request additional features, or report issues, please use the Developer Forums.
When installing CUDA Toolkit 11.5 and specifying options, be sure to select CUDA > Development > Tools > CUPTI.