The c3.large is a compute-optimized AWS EC2 instance: 2 vCPU and 3.75 GiB of memory, 1.88 GiB per vCPU. In the name, "c" stands for compute, "3" is the generation and "large" is the size within the c3 family. It runs on Intel Xeon E5-2680 v2 (Ivy Bridge) at 2.8 GHz, and AWS introduced it in November 2013. AWS has since shipped c4, c5, c6i and c7i; c4.large is the direct replacement at this size, scoring 31,679 CoreMark/s against this instance's 29,520 — roughly 7% more throughput for the same vCPU count. Rackspace Spot's ch.vs1.medium is a like-for-like substitute at 2 vCPU and 4 GiB, $0.105/hr on AWS in US East (N. Virginia), from $0.002/hr on Rackspace Spot.
Match qualityNo local disk
c3.large comes with 2 × 16 GB SSD attached to the machine. Rackspace Spot nodes use network storage only, so that disk does not come with it.
If you were using the local disk as fast scratch space — temporary files, a local cache, an index — you will need a persistent volume or object storage instead, and both are slower to read. If it was just extra space you never depended on, nothing changes.
