Meta reuses old RAM in new servers with custom bridge chip

News
Jul 3, 20262 mins

The would-be AI infrastructure provider aims to solve the problem of rising memory prices in a cost-effective way.

Meta logo on android
Credit: Sergei Elagin / Shutterstock

With the cost of new RAM soaring, Meta has found a thrifty way to reuse older memory in newer servers.

The performance of about 40% of Meta’s millions of servers is limited by a lack of memory, the company said — but it has a surplus of older DIMMs from decommissioned servers, because RAM chips can last about twice as long as the rest of the machine.

To profit from this imbalance, it developed a custom Computer Express Link (CXL) chip it calls Vistara, and associated software, to decouple older memory from server memory channels, enabling its reuse in new machines alongside their native memory. Using the older RAM with the CXL interface doesn’t significantly affect performance — although it would have done if the older DIMMs were plugged straight into newer servers.

Kudos to tech site The Register for noticing the development, which Meta described in a technical paper: Vistara: Making CXL Real — Full Path from ASIC Design and OS Support to Hyperscale Deployment,” setting out how the new technology works.

There is a particular need to be thrifty right now, given the current state of the market. Last year, users were warned that memory prices could double by the end of 2026, while the RAM shortage could last until 2027. This week, Apple suggested using cheap Chinese chips, a move that may well be frowned on by the Trump administration. The Meta development may prove to be an efficient way forward.

Maxwell Cooter

Maxwell began writing about technology in 1984, when mainframes ruled the world. Since then he has written for just about every business computing title in the UK, and for a few in the US, covering everything from Artificial intelligence to Zero-day exploits and all points in between. He has also been editor-in-chief of several award-winning titles, including Network Week, Techworld, and Cloud Pro, and a regular contributor to Whatsonstage.com. In his spare time he coaches a junior rugby team.

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