t3a.large is AWS's general-purpose EC2 size at 2 vCPU and 8 GiB. In the name, "t" is burstable, "3" is the generation, "a" marks AMD processors and "large" is the size within the t3a family. It runs on AMD EPYC 7571 at 2.5 GHz, and AWS introduced it in April 2019. AWS has since shipped t4g and t8i; t4g.large is the direct replacement at this size, scoring 39,596 CoreMark/s against this instance's 25,986 — roughly 52% more throughput for the same vCPU count. Rackspace Spot maps this to gp.vs1.large (4 vCPU, 16 GiB), giving you 2 more vCPU and 8 GiB more memory, about 85% below the US East (N. Virginia) on-demand rate.