Instances›AWS EC2›r8idb›r8idb.16xlarge
Compute
vCPUs64
Memory512 GiB
Mem / vCPU8.00 GiB
ProcessorXeon Scalable
Clock speed3.9 GHz
Architecturex86_64
Storage
Type1 × 3,800 GB NVMe SSD
Bandwidth50,000 Mbps
Throughput6250 MB/s
IOPS240,000
Networking
Performance66.66 Gigabit
Max ENIs16
IPv6Yes
GPUNone
Family sizes
r8idb.large2 vCPU · 16 GiB
r8idb.xlarge4 vCPU · 32 GiB
r8idb.2xlarge8 vCPU · 64 GiB
r8idb.4xlarge16 vCPU · 128 GiB
r8idb.8xlarge32 vCPU · 256 GiB
r8idb.12xlarge48 vCPU · 384 GiB
r8idb.16xlarge64 vCPU · 512 GiB
r8idb.24xlarge96 vCPU · 768 GiB
r8idb.32xlarge128 vCPU · 1024 GiB
r8idb.48xlarge192 vCPU · 1536 GiB
r8idb.metal-48xl192 vCPU · 1536 GiB
r8idb.96xlarge384 vCPU · 3072 GiB
r8idb.metal-96xl384 vCPU · 3072 GiB
r8idb.16xlarge

The r8idb.16xlarge is a memory-optimized AWS EC2 instance: 64 vCPU and 512 GiB of memory, 8.00 GiB per vCPU. In the name, "r" stands for RAM, "8" is the generation, "idb" marks Intel processors, local NVMe storage and block-storage optimisation and "16xlarge" is the size within the r8idb family. It runs on Intel Xeon Scalable (Granite Rapids) at 3.9 GHz, and AWS introduced it in May 2026. AWS has since shipped r9g; r9g.16xlarge is the direct replacement at this size. No single Spot node covers 64 vCPU and 512 GiB, so the equivalent is a fleet: 4 × mh.vs1.2xlarge, 64 vCPU and 512 GiB in total, $7.50/hr on AWS in US East (N. Virginia), from $0.084/hr on Rackspace Spot. Spot delivers compute as managed Kubernetes, so a node pool of that size is the native shape of the answer rather than a workaround — provided the workload scales horizontally.

Match qualityScale-out match

r8idb.16xlarge gives you 64 vCPU and 512 GiB in a single machine. The largest comparable Spot node, mh.vs1.2xlarge, is 16 vCPU and 128 GiB, so the equivalent here is 4 nodes rather than one.

Spot runs as managed Kubernetes, so a 4-node pool is the normal way to run things rather than a workaround. If your workload already sits behind a load balancer, a queue or a scheduler, it spreads across them without changes. If it needs all 64 cores and 512 GiB in one process, it does not.

No local diskr8idb.16xlarge comes with 1 × 3,800 GB NVMe SSD attached to the machine. Spot nodes use network storage only, so that disk doesn't come with it. If you were using it as fast scratch space, you'd move to a persistent volume or object storage, which are slower to read.
Pricing by region
1 hr
RegionAWS on-demandAWS Spot1-yr Reserved3-yr ReservedRackspace SpotYou save
US East, N. Virginia$7.503$2.776$0.084
$7.419 savings
US Central, Chicagono AWS region$0.084
US Central, Dallasno AWS region$0.524
Hong Kong$0.084
Sydney, Australia$0.084
London, UK$0.524
US West, San Jose$0.008
US Central, Dallas 2no AWS region$0.968
When to use it
Good for
  • ●Large JVM heaps and application servers that hold state
  • ●OLAP and business intelligence query engines
  • ●Real-time analytics over hot datasets
  • ●Workloads that fit inside 512 GiB of RAM
  • ●Jobs that want 1 × 3,800 GB of local NVMe scratch space
  • ●Network-heavy services — AWS rates this size at 66.66 Gigabit
  • ●Anything that shards cleanly across 4 nodes, which is how it maps onto Rackspace Spot
Avoid if
  • ●The working set needs more than 512 GiB of RAM
  • ●More than 8.00 GiB of RAM per vCPU is needed — that ratio is fixed for the whole family
  • ●The work is single-threaded. Most of these 64 vCPU would sit idle.
  • ●GPU or FPGA acceleration is needed
  • ●CPU-bound work. You are paying for memory this workload will not use.
r8idb.16xlarge runs $5,477/mo on AWS on-demand. The 4-node equivalent on Rackspace Spot: $61/mo.
  • Spot sells spare capacity at market prices. It is the cheapest compute on the internet.
  • Prices are set by supply and demand. You pay what the market decides.
  • Compute is delivered as fully managed Kubernetes. All infrastructure is taken care of.
  • Egress costs $0.01/GB after the free allowance. AWS charges $0.09/GB.
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