1.20.0-rc1 (Dec 2 2025)
Features:
UCP
- Added new GPU device API for direct GPU-to-GPU communication
- Added host API for GPU device management
- Added device signaling API with cooperation levels and flags
- Added API for working with offsets and channel id in device operations
- Added method to write to local counter in device operations
- Added local and remote address fields to memory list element in device API
- Added device lane selection and allocated handle population
- Added support for Direct NIC (DPU) data path with CUDA
- Added rkey packing support for Direct NIC
- Added sender flush mechanism when memory sys_dev differs from remote lane sys_dev
- Added option to use single network device per protocol
- Added MIN_RMA_CHUNK_SIZE configuration parameter
- Decreased default value for MIN_RMA_CHUNK_SIZE from 16k to 8k
- Improved protocol lane selection with find_lanes callback to minimize overhead
- Improved send-zcopy latency factor for fast-completion cases
- Improved multi-ppn performance estimation
- Removed deprecated ucp_mem functions
- Deprecated ucp_request_alloc API
UCT
- Added new device API for GPU communication (rc_gda transport)
- Added GDAKI transport with endpoint export to GPU
- Added DEVX QP/CQ support on foreign memory
- Added device API implementation for CUDA_IPC transport
- Added device put multi, put partial, and atomic operations for CUDA_IPC
- Added peer failure error handling capability for GDAKI
- Added check for nvidia_peermem driver when using GDA transport
- Enabled Direct NIC by default for IB transport
- Added XDR performance recognition
- Added support for mapping DMA_BUF handle via PCIe for Direct NIC
- Improved GDR_COPY performance with fast-path cache lookup
RDMA CORE (IB, ROCE, etc.)
- Added ConnectX-9 device support
- Split dp_ordering flag for DV/DevX transports
- Added VRF tables support for RoCE reachability check
- Added EFA-specific GPUDirect support detection
TCP
- Added routing table check during reachability verification
UCS
- Introduced lightweight rwlock data structure
- Added built-in atomics for rcache rwlock
- Improved VFS symlink paths and duplicate object handling
- Disabled error signal interception by default
CUDA
- Added wrappers for NVML functions
- Added hook for cuLibraryGetGlobal
- Improved CUDA call logging
- Improved source/destination memory type detection for lane performance estimation
- Removed unsafe usage of cuCtxGetId
- Added support for cuCtxCreate_v4 for newer CUDA versions
- Improved context management for CUDA_IPC operations
UCM
- Changed module info print to debug level by default
Tools
- Added GDAKI kernel option to perftest
- Added UCP cuda device tests to perftest
- Added MPI+CUDA example
- Differentiated wakeup feature and extra info options in perftest
Build
- Added ability to build CUDA device code for supported architectures
- Added ucx.spec into tarball for Universal Build System support
- Added CUDA 13 support
- Added GDA build failure when gpunetio not found
Packaging
- Moved driver level dependencies under Recommends section in Debian packages
- Added Provides field for upstream packages in Debian
- Migrated JUCX publish from OSSRH to Central Portal
- Added ib-mlx5-gda separate package
CI/Testing
- Added Rocky OS support to release pipeline
- Added RHEL 10 containers to build matrices
- Added Debian 13 to CI build stage
- Added ARM build testing
- Switched to MOFED 25.07
- Switched GPU tests to Ubuntu 24.04 DOCA 3.1 (GPUNetIO) image
- Added support for nvidia_peermem module in testing
- Disabled Valgrind in CI Tests stage
- Disabled tag matching offload tests
GO Bindings
- Made go bindings thread safe
Documentation
- Added note about reachability check mode in README
- Mentioned nvlink as supported transport
- Documented return status for device APIs
AWS EFA
- Added RMA WRITE operations support
- Added flush and fence operations for SRD
- Enabled EFA SRD support in tests
Bugfixes:
UCP
- Fixed fallback to blocking registration for network device only
- Fixed flush_state validity check before using it
- Fixed single net dev filtering for single proto
- Fixed rkey size estimation for rendezvous
- Fixed memory invalidation without RNDV
- Fixed gather_pending_requests to execute only when reconfig occurs
UCT
- Fixed CUDA_IPC protocol selection for cuda_ipc
- Fixed GDA compilation issues
- Fixed GDAKI wqe_idx overflow
- Fixed MM FIFO room calculation for tail > head case
- Fixed CUDA_IPC indices handling in put partial
- Removed DOCA runtime dependency from GDAKI
- Fixed GDA log spam by reducing DOCA log level
- Fixed UAR support check when querying resources for GDA/MLX5
- Fixed crash in GGA transport when EXPORTED_MKEY flag is missing
CUDA
- Fixed stack overflow bug when calling cuPointerGetAttribute
- Fixed mapping of DMA_BUF handle for Direct NIC
- Returned object to mpool in case of failure in CUDA_COPY
- Reduced log level of rkey unpacking failures
- Handled cuMemRelease error status properly
- Fixed context setting for local buffer in CUDA_IPC
- Fixed host unregister error message (changed to diagnostic)
- Fixed CUDA_IPC header installation
RDMA CORE (IB, ROCE, etc.)
- Fixed RoCE network device name reading
- Fixed Direct NIC related issues
- Reverted RC EP address size adaptation without flush_rkey
UCS
- Fixed ARCH header inclusion when building with nvcc (arm_neon.h)
- Fixed VFS symlink path handling
- Fixed netlink message receiving to continue until 'done' flag is set
Build
- Fixed NVCC search with explicit --with-cuda
- Fixed ZE transport build failures
- Fixed ucs_arch_get_cpu_flag compilation
- Fixed CUDA device code build for supported architectures
Testing
- Fixed test_jenkins CI issues
- Decreased rwlock test duration
- Fixed error counting in gtest
- Enabled retries for test_arch.memcpy
- Fixed test_cuda_nvml condition relaxation
- Skipped build when generating packages
- Fixed CUDA device restoration in tests
- Improved error detection in UCP device tests
- Fixed global topo state cleanup during gtest
Tools
- Fixed perftest CUDA kernel issues
GO Bindings
- Fixed go bindings compilation with CUDA
IB/EFA
- Fixed error message when FLID is not available
Packaging
- Fixed RPM SPEC debug_package macro execution on SLES16