+.. option:: gpu_dev_ids=str : [libcufile]
+
+ Specify the GPU IDs to use with CUDA. This is a colon-separated list of
+ int. GPUs are assigned to workers roundrobin. Default is 0.
+
+.. option:: cuda_io=str : [libcufile]
+
+ Specify the type of I/O to use with CUDA. Default is **cufile**.
+
+ **cufile**
+ Use libcufile and nvidia-fs. This option performs I/O directly
+ between a GPUDirect Storage filesystem and GPU buffers,
+ avoiding use of a bounce buffer. If :option:`verify` is set,
+ cudaMemcpy is used to copy verificaton data between RAM and GPU.
+ Verification data is copied from RAM to GPU before a write
+ and from GPU to RAM after a read. :option:`direct` must be 1.
+ **posix**
+ Use POSIX to perform I/O with a RAM buffer, and use cudaMemcpy
+ to transfer data between RAM and the GPUs. Data is copied from
+ GPU to RAM before a write and copied from RAM to GPU after a
+ read. :option:`verify` does not affect use of cudaMemcpy.
+
+.. option:: pool=str : [dfs]
+
+ Specify the UUID of the DAOS pool to connect to.
+
+.. option:: cont=str : [dfs]
+
+ Specify the UUID of the DAOS container to open.
+
+.. option:: chunk_size=int : [dfs]
+
+ Specificy a different chunk size (in bytes) for the dfs file.
+ Use DAOS container's chunk size by default.
+
+.. option:: object_class=str : [dfs]
+
+ Specificy a different object class for the dfs file.
+ Use DAOS container's object class by default.
+