Meta Reuses Old RAM in New Servers with Custom Bridge Chip
Facing soaring memory prices, Meta has engineered a custom Computer Express Link chip called Vistara to repurpose older RAM in its latest servers. This innovative approach allows the company to utilize surplus memory from decommissioned machines alongside native memory without significantly impacting performance, effectively solving a critical bottleneck for its AI infrastructure.
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.
- snowwrestler
At the beginning of William Gibson’s Neuromancer, the protagonist is trying to sell 3 MB of RAM in underground markets. This is often cited as one of the ways the book has not aged well. But, looking at the direction of the memory market now… maybe we just haven’t gotten there yet.
- rob74
Why not go directly to the source article that has a lot more details?
https://www.theregister.com/systems/2026/06/29/zuck-saves-me...
- kjs3
I have always wondered why there was never a big market[1] for "cheap PCI/PCI-X/PCI-e card you can stick a boatload of your old/surplus/n-generation old simms/dimms on and use as swap/slow memory/ram disk/etc". It's rare you can populate a motherboard with a full address space full of 'new' memory, and you can teach kernels to prefer some memory to others because of speed[2], so it seems like a no-brainer.
I seem to remember the market for doing similar with flash got neutered over patent issues, but I can't recall the details. And flash cache did end up being a market, at least for bigger players. Maybe something similar happened here, or maybe it just hit a niche I cared about at the time?
[1] I know there were a handful of products in this space, but my impression is they never really took off. I could be wrong.
[2] Definitely can in NetBSD; I've done it for archs like VMEbus where it's common to have a small, fast on board memory and much slower, often larger memory out on the bus. I assume this sort of thing is enabled in Linux by the work to support NUMA, but I've never looked into it.
- lizknope
There are standard product CXL memory expander chips if you don't want to design a custom chip.
- rock_artist
The interesting part of this "RAM crisis" is similar to other fields where a problem results multiple parties looking for alternative solutions.
This yields for exciting ideas or workarounds that might result a post-crisis memory boom (hopefully) also for local machines.
1. Lowest, Apple is evaluating new Chinese manufacturer which means change of supply demand if indeed it has reasonable QA. (https://www.ft.com/content/f4ac5c92-03be-4499-b16a-017a7e9ee...)
2. Companies tries to workaround performance - suddenly single channel is 'ok' ? :)
- jzb
It’d be nice if there were a consumer version of this. I have plenty of old RAM.
- ateles
ServeTheHome already reported on CLX memory expansion controllers back in December:
https://www.servethehome.com/hyper-scalers-are-using-cxl-to-...
- westurner
ScholarlyArticle: "Vistara: Making CXL Real—Full Path from ASIC Design and OS Support to Hyperscale Deployment" (2026) https://aisystemcodesign.github.io/papers/isca26/vistara_cam...
TIL there are 2x 2.5GbE PCI-E HAT adapters for Pi 5.
How to attach RAM to the new NVLink/UALink fiber buses?