What is the difference between thrust::host_vector and std::vector?

Question

Both allocate memory on the host and I can copy contents to device_vector and back using iterators. Why was host_vector necessary to include in the API? Does it have something to do with pinned memory?

Answer 1

No, it doesn't implement pinned memory.

I suspect it exists to implement a few overrides, such as assignment from a device_vector.

Also, unlike, the std::vector implementation in MSVC, Thrust's host_vector doesn't check iterator validity which leads to much faster performance on debug builds (by default).