[SPDK] How to accelerate the speed of constructing spdk nvme disk ?

Hello all,
     Because there are many disks in our system and the startup time is
important for us. So we measured the speed of construct nvme disk in spdk
.We found it is about  220ms for construct a disk. ie.
The total time for construct total N nvme  disks is   (2.2 +0.22 *N )
second. The total construct disk time is linear increased when disk number
increases.

     Then we detail analysis where the time is spent. We found the time is
spent in two ioctl

(1) ioctl(vfio_group_fd, VFIO_GROUP_GET_DEVICE_FD, dev_addr)   --->  110ms
(2)ioctl(vfio_dev_fd, VFIO_DEVICE_RESET)   ---> 110ms

But the speed of constructing nvme disk is too slow for us.
Does anyone can give us suggestion for speedup nvme disk construction in
spdk??
Any suggestion is appreciated.
Thank you.