Instances›AWS EC2›x2gd›x2gd.4xlarge
Compute
vCPUs16
Memory256 GiB
Mem / vCPU16.00 GiB
ProcessorGraviton2 Processor
Clock speed2.5 GHz
Architecturearm64
Storage
Type1 × 950 GB NVMe SSD
Bandwidth4,750 Mbps
Throughput593.75 MB/s
IOPS20,000
Networking
PerformanceUp to 10 Gigabit
Max ENIs8
IPv6Yes
GPUNone
Family sizes
x2gd.medium1 vCPU · 16 GiB
x2gd.large2 vCPU · 32 GiB
x2gd.xlarge4 vCPU · 64 GiB
x2gd.2xlarge8 vCPU · 128 GiB
x2gd.4xlarge16 vCPU · 256 GiB
x2gd.8xlarge32 vCPU · 512 GiB
x2gd.12xlarge48 vCPU · 768 GiB
x2gd.16xlarge64 vCPU · 1024 GiB
x2gd.metal64 vCPU · 1024 GiB
x2gd.4xlarge

x2gd.4xlarge is AWS's memory-optimized EC2 size at 16 vCPU and 256 GiB. In the name, "x" is the extra-memory line, "2" is the generation, "gd" marks AWS Graviton (ARM) processors and local NVMe storage and "4xlarge" is the size within the x2gd family. It runs on AWS Graviton2 Processor at 2.5 GHz, and AWS introduced it in March 2021. AWS has since shipped x8i; x8i.4xlarge is the direct replacement at this size, scoring 384,631 CoreMark/s against this instance's 317,523 — roughly 21% more throughput for the same vCPU count. The closest Spot shape is mh.vs1.2xlarge at 16 vCPU, so this instance maps to 2 of them — 32 vCPU and 256 GiB across the fleet, $1.34/hr on AWS in US East (N. Virginia), from $0.042/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

x2gd.4xlarge gives you 16 vCPU and 256 GiB in a single machine. The largest comparable Spot node, mh.vs1.2xlarge, is 16 vCPU and 128 GiB, so the equivalent here is 2 nodes rather than one.

Spot runs as managed Kubernetes, so a 2-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 16 cores and 256 GiB in one process, it does not.

x86_64 onlyx2gd.4xlarge is Graviton (arm64) and Rackspace Spot has no arm64 nodes, so you'd be moving to x86. You'll need x86 builds of your images, and per-core speed differs between the chips — worth testing before you decide how many nodes to run.
No local diskx2gd.4xlarge comes with 1 × 950 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$1.336$0.220$0.823$0.456$0.042
$1.294 savings
US Central, Chicagono AWS region$0.042
US Central, Dallasno AWS region$0.262
Hong Kong$0.042
Sydney, Australia$0.042
London, UK$0.262
US West, San Jose$0.004
US Central, Dallas 2no AWS region$0.484
When to use it
Good for
  • ●OLAP and business intelligence query engines
  • ●Real-time analytics over hot datasets
  • ●Database instances that keep the working set in RAM
  • ●Workloads that fit inside 256 GiB of RAM
  • ●Jobs that want 1 × 950 GB of local NVMe scratch space
  • ●Network-heavy services — AWS rates this size at Up to 10 Gigabit
  • ●Anything that shards cleanly across 2 nodes, which is how it maps onto Rackspace Spot
Avoid if
  • ●The working set needs more than 256 GiB of RAM
  • ●You cannot rebuild x86-only binaries or vendor images for aarch64
  • ●CPU-bound work. You are paying for memory this workload will not use.
  • ●More than 16.00 GiB of RAM per vCPU is needed — that ratio is fixed for the whole family
  • ●The work is single-threaded. Most of these 16 vCPU would sit idle.
  • ●GPU or FPGA acceleration is needed
$975/mo on AWS on-demand against $31/mo on Rackspace Spot for the 2-node equivalent — market-priced, not list-priced.
  • 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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