Using mmap on index

[lzuwei]

Is it possible to use a memory mapped file to store the index (eg: mmap) on a hnsw index, this is to reduce the memory usage size of a large index.

[yurymalkov]

It is possible, but not yet implemented. The easiest way to do it is to memmap the saved file.
I would expect it to cause big performance losses even on fast SSDs.