At OCP Summit 2023, Meta and AMD confirmed off a demo of CXL Reminiscence, or a Kind-3 system. We noticed this in a nook of the present ground and figured we might give it some protection since we beforehand lined QCT demoing Astera Labs Leo CXL Reminiscence Growth on Intel Sapphire Rapids at SC22. It’s a bit unusual, however whereas AMD EPYC 9004 “Genoa” processors assist CXL, a lot of the Kind-3 reminiscence system demos now we have seen thus far have used the Sapphire Rapids Intel Xeon which doesn’t assist CXL Kind-3 units (however they work.) It was nice to see AMD with a hyper-scale demo.
Meta AMD CXL 2.0 Reminiscence Growth Demo at OCP Summit 2023
Right here was the demo board which was fairly simple to overlook. It has 4 DIMM slots after which a chip within the center.
On the far finish of the board you may see a PCIe x16 connector.
We requested the oldsters staffing the demo which CXL chip is getting used. Usually we see Astera Labs or Microchip today. The representatives declined to inform us who makes the chip beneath the warmth sink and fan.
Since this was an AMD demo, we see a twin SP5 socket system with a enjoyable array of followers over the DIMM slots and liquid cooling for the CPUs.
The CXL reminiscence growth demo board is plugged right into a PCIe Gen5 slot within the growth space. One may also discover that the. DDR5 slots on the motherboard are populated with solely two DIMMs in addition the system.
Remaining Phrases
CXL reminiscence growth units serve two functions. First, they’ll add reminiscence capability and bandwidth to methods, increasing the capabilities of these methods. Second, and essential for an organization like Meta, CXL Kind-3 units are being checked out as a technique to re-use DRAM. If you consider what number of DIMMs that hyper-scalers like Meta use, then the chance to make reminiscence controllers that may interface between DDR4 or DDR5 in the present day on one finish and CXL on the opposite finish provide an infinite alternative for price financial savings. For some perspective, many units inside a system, are nonetheless utilizing DDR4 although trendy server CPUs have transitioned to DDR5. Reminiscence is commonly a prime, or close to the highest, knowledge heart {hardware} expense merchandise, so discovering a technique to tier reminiscence to slower capability tiers over CXL has numerous promise.
Now, what we actually wished to see was a MI300 with CXL reminiscence growth, however that must wait till December it appears.
