What is the largest database using an Open Source DBMS?
by Todd Ogasawara
Related link: http://www.wintercorp.com/
Slashdot World's Largest Databases Ranked thread
discusses the Winter Corp.'s top 10 largest database list. When you look at the list, you'll see that all the DBMS engines are commercial engines.
So, what are the top 10 largest databases using Open Source DBMSes?
"Mytrix Inc. for example, is maybe the largest MySQL database site in the world, storing more than a terabyte of data."
"American Chemical Society - [...] Their Journal Archive stores 125 years of full publications (2.5 million pages, more than 1 terabyte of data) using PostgreSQL."
Not relational but still a largely open source db:
"[The Wayback Machine is] a computer system with close to 400 parallel processors, 100 terabytes of disk space, hundreds of gigs of RAM, all for under a half-million dollars.[...]We use as much open source software as we can; we make as much of our software as we can open because we're a library."
(this one wouldn't feature in the list despite its size because it doesn't need to handle a high transaction volume)