Hi Amirouche,

> So there needs to be some smarter solution, one that we'd unlike to develop inhouse

Big cat, small fish. As wikidata continue to grow, it will have specific needs.

Needs that are unlikely to be solved by off-the-shelf solutions.

Are you suggesting to develop the database in-house? even MediaWiki uses MySQL

> but one that has already been verified by industry experience and other deployments.

FoundationDB and WiredTiger are respectively used at Apple (among other companies)

and MongoDB since 3.2 all over-the-world. WiredTiger is also used at Amazon.

Let`s not talk about MongoDB, it is irrelevant and very mixed. Some say it is THE solution for scalability, others have said it was the biggest disappointment.

Do FoundationDB and WiredTiger have any track record for hosting open data projects or being chosen by open data projects? PostgreSQL and MySQL are widely used, e.g. OpenStreetMaps. Virtuoso by DBpedia, LODCloud cache and Uniprot.

I don know FoundationDB or WiredTiger, but in the past there were often these OS projects published by large corporations that worked in-house, but not the OS variant. Apache UIMA was one such example. Maybe Blazegraph works much better if you move to Neptune, that could be a sales hook.

Any open data projects that are running open databases with FoundationDB and WiredTiger? Where can I query them?

> "Evaluation of Metadata Representations in RDF stores"

I don't understand how this is related to the scaling issues.

Not 100% pertinent, but do you have a better paper?

> [About proprietary version Virtuoso], I dare say [it must have] enormous advantage for us to consider running it in production.

That will be vendor lock-in for wikidata and wikimedia along all the poor souls that try to interop with it.

Actually Uniprot and Kingsley suggested to host the OS version. Sounded like this will hold for 5 more years, which is probably the average lifecycle. There is also SPARQL, which normally doesn`t do vendor lock-ins. Maybe you mean that nobody can rent 15 servers and install the same setup as WMF for Wikidata. That would be true. Switching always seems possible though.