Can the index file generated in version 1.7.4 be used in version 1.9.0

[rose839]

Summary

I generated a vector index file using the following C++code on Faiss version 1.7.4:

faiss::IndexFlatL2 indexa = faiss::IndexFlatL2(d);
faiss::IndexIVFScalarQuantizer index = faiss::IndexIVFScalarQuantizer(&indexa,d,nlist,faiss::ScalarQuantizer::QuantizerType::QT_8bit); 

index.train(len,vdatas);
index.add(len,vdatas);

faiss::write_index(&index, "ivfsq8.index");

Can I load and use the generated index file "ivfsq8.index" on Faiss version 1.9.0？

Platform

OS: linux

Faiss version: 1.7.4 1.9.0

Installed from: compiled by myself

Faiss compilation options: ignore

Running on:

• CPU
• GPU

Interface:

• C++
• Python

Reproduction instructions

ignore

[mnorris11]

Hi @rose839, does this not work for you?

index_read and index_write should be backwards compatible. If a field is removed then it has to read/write a dummy, like in #3692.

[rose839]

I did a simple test, it works between 1.7.4 and 1.9.0。Thank you very much。