
Storage spent most of the last two decades as the part of the server nobody had to think about very hard. It was evaluated on capacity, reliability and cost per gigabyte, and the interesting engineering happened elsewhere. That is not where the industry is today. As deployments shift from training to inference, the question of where a model keeps its working context has become a performance problem with real money attached to it. I recently sat down with Garrett McKibben, senior director of technical marketing at Graid Technology, to talk about what inference workloads are doing to the memory and storage hierarchy. Garrett and I have been talking about the blending of that hierarchy for a long time, and this conversation was the first one where the economics of it felt concrete.
Graid Technology has been in market for about five or six years, built around a premise that sounds almost contrarian: remove the RAID controller entirely, let host memory talk directly to the SSDs, and accelerate the I/O path with the GPU. The reason comes down to arithmetic.
“Any single PCIe by 16 Gen 4 was limited to 30 gigs of throughput. Gen 5 is limited to 60 gigs of throughput,” Garrett said. “The analogy we like to use is you've got a four lane highway and to get to your storage, you have to go down to a one lane bridge.”
Buyers have invested heavily in NVMe performance, then sipped it through what he called a tiny coffee straw. That mismatch was the company’s original opening. It has since expanded. The company acquired the VROC assets from Intel roughly a year ago, with VROC by Graid Technology arriving in the coming months. Now it is pointing its efforts toward applying the same I/O thinking from its founding to agentic AI and KV cache.
As attention shifts from training to inference, the gating factor is not compute. Garrett pointed instead at capacity and the cost per gigabyte across the hierarchy. HBM on a Blackwell part tops out near 180 gigabytes at $50 to $80 per gigabyte. System DRAM improves the economics at $5 to $8 per gigabyte but remains finite. NVMe runs $0.08 to $0.12 per gigabyte with effectively unbounded capacity.
The instinct when a model runs out of room for its KV cache is to add GPU memory. Garrett’s math says that path closes quickly.
“With that limited amount of HBM, in our calculations, you run out of concurrent users after about three or four users,” he said. “As much as maybe NVIDIA would love each of us to go buy a new Blackwell 200 for every three users, it’s not feasible.”
The test for any storage tier in this role is simple to state and harder to satisfy. A GPU that loses its context can always recompute it, and it does so quickly. Storage only earns its place when retrieval beats recalculation.
“Fundamentally, fetch has to be faster than recompute,” Garrett said. “If it takes longer for the GPU to go fetch it…than it takes to compute, then there’s no value.”
Graid Technology published results measuring exactly that. With no KV Cache, recomputation took 29.5 seconds; adding MD RAID raised it to 36.6 seconds. SupremeRAID reduced the KV-cache retrieval path to 9 seconds—3.2x faster than recomputing the context. Garrett was careful not to oversell the finding, noting it holds in that particular scenario rather than every case, but the direction is the point: with an unconstrained link to NVMe and long context windows, fetching wins.
The GPU-side approach costs less than most people assume. The software-only version runs on the GPUs already in the box, consuming roughly 4 percent of capacity, about six streaming multiprocessors, and releasing them the moment the I/O completes. That leaves the CPU free for the applications it is increasingly responsible for orchestrating.
The shift from components to rack-level systems makes the storage question harder rather than easier. A request may be initiated on one GPU and serviced elsewhere, which means the context has to be findable across the rack or the pod without adding back the latency the design was meant to remove. Graid Technology is working with open source frameworks including LMCache and Mooncake toward a single namespace that can meet those latency requirements.
Garrett framed why any of this matters with a simple metaphor. He compared a GPU without its KV cache to walking into a room and forgetting why you went in, then having to retrace your steps. With agentic workloads running for hours or days, that retracing is not a minor inefficiency.
“There’s a difference between having them fully utilized recalculating the same thing time and time again versus retrieving it and then moving to the next step,” he said. “It’s no longer about FLOPS. It's about enabling your engineers or your users to get results through their agents.”
The blending of the memory and storage hierarchy has been a talking point for the better part of a decade. KV cache overflow now gives it a number attached to it. Fetch versus recompute is a clean test, and it changes the buying conversation: a team with a system that retrieves context instead of recomputing it is not saving on storage, it is recovering GPU cycles it already paid for. That is a materially different business case, and it lands with a different set of decision makers.
The open question is rack scale. Single-server results are encouraging, but inference is becoming a distributed problem, and locating a given KV cache across a pod without reintroducing latency remains unsolved. We’ll be watching which approaches holds up as the unit of deployment keeps getting bigger.