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Transparent memory offloading: more memory at a fraction of the cost and power

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Re: Transparent memory offloading: more memory at a fraction of the cost and power

#61

Post by csdvrx » Tue, Jun 21, 2022, 7:53 PM UTC

fulafel wrote: post #28

csdvrx wrote: post #19

Personally, I want to see PCIe x16 devices (or U2 NVMe) where you can plug a few sticks of RAM to get a temporary volume. It would be ideal for caching!

What would be the advantage vs DIMMs?

In a server, you're more limited by DIMM slots than by PCIe ports, especially on EPYC considering the number of lanes available.

With the shift towards DDR5, DDR4 could be repurposed as old servers are decommissioned.

Re: Transparent memory offloading: more memory at a fraction of the cost and power

#62

Post by fulafel » Wed, Jun 22, 2022, 2:28 PM UTC

csdvrx wrote: post #61

fulafel wrote: post #28

Earlier quoted context omitted.

What would be the advantage vs DIMMs?

In a server, you're more limited by DIMM slots than by PCIe ports, especially on EPYC considering the number of lanes available. With the shift towards DDR5, DDR4 could be repurposed as old servers are decommissioned.

I'm not convinced of the limited slots point - 16 (AMD) / 24 (Intel) DIMM slots in commodity single cpu socket server mobos, it gets you a few TB of RAM. 48 sockets in multi CPU socket mobos if you need more.

I can see "recycling refurbished previous-gen DIMMs" working for certain cases but it sounds a bit niche unless someone productises it really well.

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