“Motherboard spoke to the Barcelona Supercomputing Center about how it outfitted a deconsecrated 19th century chapel to host the MareNostrum 4 — the 25th most powerful supercomputer in the world,” writes Slashdot reader dmoberhaus. From the report: Heralded as the “most beautiful data center in the world,” the MareNostrum supercomputer came online in 2005, but was originally hosted in a different building at the university. Meaning “our sea” in Latin, the original MareNostrum was capable of performing 42.35 teraflops — 42.35 trillion operations per second — making it one of the most powerful supercomputers in Europe at the time. Yet the MareNostrum rightly became known for its aesthetics as much as its computing power. According to Gemma Maspoch, head of communications for Barcelona Supercomputing Center, which oversees the MareNostrum facility, the decision to place the computer in a giant glass box inside a chapel was ultimately for practical reasons.
“We were in need of hundreds of square meters without columns and the capacity to support 44.5 tons of weight,” Maspoch told me in an email. “At the time there was not much available space at the university and the only room that satisfied our requirements was the Torre Girona chapel. We did not doubt it for a moment and we installed a supercomputer in it.” According to Maspoch, the chapel required relatively few modifications to host the supercomputer, such as reinforcing the soil around the church so that it would hold the computer’s weight and designing a glass box that would house the computer and help cool it. The supercomputer has been beefed up over the years. Most recently, the fourth iteration came online in 2017 “with a peak computing capacity of 11 thousand trillion operations per second (11.15 petaflops),” reports Motherboard. “MareNostrum 4 is spread over 48 server racks comprising a total of 3,456 nodes. A node consists of two Intel chips, each of which has 24 processors.”