remove_ids not implemented for GpuIndex?

[orihabAnyvision]

UPDATE: I see I can transfer the index back to the cpu, remove the vectors, and transfer back. Seems inefficient for an index of a couple mil.. any other suggestions?

I'm getting the error:
Error in virtual size_t faiss::Index::remove_ids(const faiss::IDSelector&) at /faiss/faiss/Index.cpp:43: remove_ids not implemented for this type of index

I tried to have a look at the code but.. Is it true that remove_ids isn't implemented for GPUIndex? Is there a specific reason for this? Is there a reason its difficult to do?

Any suggestion how I can get around this? or some direction into implementing myself?

My use case is creating an IDIndexMap over a FlatIndex, and then transferring the IndexMap to the GPU. I wrote go bindings for it and it works great and performace is blazing fast but I cant remove specific vectors from the index... ?