pytorch

a09e1098 - Profiling allocator for mobile. (#43951)

Profiling allocator for mobile. (#43951) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/43951 AllocationPlan: Stores the sequence of allocations, their sizes and liftime of the allocations. Along with this it also stores the total size of a single memory blob, total_size, required to satisfy all the allocations. It also stores the offsets in the blob, of size total_size, corresponding to each allocation. Thus allocation plan contains: - allocation sizes - allocation lifetimes - allocation offsets - total size AllocationPlaner: Takes a pointer to the allocation plan and fills it ups with plan, i.e. sizes, lifetimes, offsets, total size. This is done via WithProfileAllocationsGuard which takes in AllocationPlan* and constructs AllocationPlanner* and set the thread local allocation_planner to it. MobileCPUAllocator profiles allocations via allocation_planner. In WithValidateAllocationsGuard, allocations profiled in the allocation plan are validated. CPUProfilingAllocator: Application owns CPUProfilingAllocator Using WithProfilingAllocatorGuard, it passes both CPUProfilingAllocator and AllocationPlan created earlier. Then CPUProfilingAllocator will manage allocations and frees according to the plan. Allocations that are not managed by CPUProfilingAllocator will be routed through c10::alloc_cpu, c10::free_cpu. Test Plan: cpu_profiling_allocator_test on mobile. Imported from OSS Reviewed By: dreiss Differential Revision: D23451019 fbshipit-source-id: 98bf1dbcfa8fcfb83d505ac01095e84a3f5b778d