b9274
server : free draft/MTP resources on sleep to fix VRAM leak (#23461)
The destroy() function in server_context_impl only cleaned up the main model and context (via llama_init.reset()) but did not free the speculative decoder (spec), draft context (ctx_dft), or draft model (model_dft).
For MTP (Multi-Token Prediction) models, ctx_dft holds GPU-allocated resources (KV cache, compute buffers) that are not freed when entering the sleeping state. On each sleep/resume cycle, new resources are allocated without the old ones being freed, leading to a VRAM leak that eventually crashes the server with out-of-memory errors.
Fix by explicitly resetting spec, ctx_dft, and model_dft in destroy() before resetting llama_init, ensuring proper cleanup order to avoid use-after-free.
ref: https://github.com/ggml-org/llama.cpp/issues/23395
Assisted-by: llama.cpp:local pi
macOS/iOS:
- macOS Apple Silicon (arm64)
- macOS Apple Silicon (arm64, KleidiAI enabled)
- macOS Intel (x64)
- iOS XCFramework
Linux:
- Ubuntu x64 (CPU)
- Ubuntu arm64 (CPU)
- Ubuntu s390x (CPU)
- Ubuntu x64 (Vulkan)
- Ubuntu arm64 (Vulkan)
- Ubuntu x64 (ROCm 7.2)
- Ubuntu x64 (OpenVINO)
- Ubuntu x64 (SYCL FP32)
- Ubuntu x64 (SYCL FP16)
Android:
Windows:
- Windows x64 (CPU)
- Windows arm64 (CPU)
- Windows x64 (CUDA 12) - CUDA 12.4 DLLs
- Windows x64 (CUDA 13) - CUDA 13.1 DLLs
- Windows x64 (Vulkan)
- Windows x64 (SYCL)
- Windows x64 (HIP)
openEuler: