With an m4.16xl, there's no effective difference between a dedicated or default tenancy instance - only one .16xl can run on a physical hypervisor, which is ref

With an m4.16xl, there's no effective difference between a dedicated or default tenancy instance - only one .16xl can run on a physical hypervisor, which is reflected in the pricing, it's $3.20/hour whether it's dedicated or not: https://aws.amazon.com/ec2/pricing/on-demand/ https://aws.amazon.com/ec2/pricing/on-demand/ https://aws.amazon.com/ec2/purchasing-options/dedicated-instances/ https://aws.amazon.com/ec2/purchasing-options/dedicated-inst... For smaller instances, there is around a 10% increase for dedicated, for example, for an m4.4xl, the price goes to $0.88 for dedicated tenancy versus $0.80 for default. There is a $2/hour fee for each region in which you have dedicated instances, but that gets lost in the noise if you're using significant AWS resources. (it's $2/hour regardless of how many instances you're running) We haven't noticed any significant difference between performance on dedicated and non-dedicated instances, and only use dedicated instances where required for compliance/regulatory reasons.