llama.cpp

3fc4e105 - sched : reintroduce less synchronizations during split compute (#20793)

sched : reintroduce less synchronizations during split compute (#20793) * CUDA: Improve performance via less synchronizations between token (#17795) * Adds CPU-to-CUDA copy capability to ggml_backend_cuda_cpy_tensor_async() * Adds function to relax sync requirements between input copies on supported backends (CUDA for now) * Exchanges synchronous copy with async copy function. * Adds macro guards to allow compilation in non-CUDA builds * Reworked backend detection in ggml-backend.cpp to avoid linking conflicts * Relax requirement of checks in async CUDA copies from backend and buffer type to just buffer type, to avoid linking issues * Minor cleanup * Makes opt-in to relax use of explicit syncs more general. Backends like vulkan which require a synchronization between HtoD copies and graph execution could also adopt this change now. * Reintroduces stricter check for CPU->CUDA backend async copy via GGML_DEVICE_TYPE_CPU. * Corrects initialization of ggml_backend_sync_mode in ggml_backend_sched_split initialization * Simplifies synchronizations to adhere to `saaasg` pattern. * Apply suggestion from @ggerganov (src->buffer to buf_src) Co-authored-by: Georgi Gerganov <ggerganov@gmail.com> * Apply suggestion from @ggerganov (src->buffer to buf_src) v2 Co-authored-by: Georgi Gerganov <ggerganov@gmail.com> --------- Co-authored-by: Georgi Gerganov <ggerganov@gmail.com> * Apply suggestions from @johannesgaessler code review Co-authored-by: Johannes Gäßler <johannesg@5d6.de> * Adds single-GPU synchronizations to multi-GPU settings to fix hip backend pipeline parallel bugs. * Scheduler Hardening: Exclude hip/MUSA from copy_from_host CPU split -> GPU split optimization * Scheduler Hardening: Re-adding original additional synchronizations for non-async backends * Adds disclaimer to hip/musa exclusion of copy_from_host. Highlights that it is out of precaution, but that no perf-impact is visible, and that it can be revisited separately anytime. --------- Co-authored-by: Georgi Gerganov <ggerganov@gmail.com> Co-authored-by: Johannes Gäßler <johannesg@5d6.de>