dpctl.memory v s Rapids Memory Manager (RMM)

RMM implements DeviceBuffer which is Cython native class wrapping around something similar to std::vector<unsigned char, custom_cuda_allocator (calls resource manager)> which is called device_buffer.

DeviceBuffer stores a unique pointer to an instance of this class. DeviceBuffer implements __cuda_array_interface__. Direct constructors always allocate new memory and copy provided inputs into the newly allocated array.

Zero-copy construction is possible from a unique_ptr<device_ buffer>, with the ownership being moved to the Cython extension instance.

DeviceBuffer provides __reduce__ method to support pickling (which works by copying content of the device buffer to host) and provides the following set of routines, among others:

• copy_to_host(host_buf_obj) to copy content of the underlying device_buffer to a host buffer
• copy_from_host(host_buf_obf) to copy content of the host buffer into memory of underlying device_buffer
• copy_from_device(cuda_ary_obj) to copy device memory underlying cuda_ary_obj Python object implementing __cuda_array_interface__ to the memory underlying DeviceBuffer instance.

RMM's methods are declared nogil.