Retrieve the number of values currently stored in the
allocator params array of the query's structure.
If no memory allocator is specified, the downstream element can handle
the default memory allocator. The first memory allocator in the query
should be generic and allow mapping to system memory, all following
allocators should be ordered by preference with the preferred one first.
Retrieve the number of values currently stored in the allocator params array of the query's structure.
If no memory allocator is specified, the downstream element can handle the default memory allocator. The first memory allocator in the query should be generic and allow mapping to system memory, all following allocators should be ordered by preference with the preferred one first.