AWS r6id.largevsAWS r6id.xlarge

r6id.large pairs 2 vCPUs with 16GB of RAM at $0.1512/hr On-Demand (about $109/mo at 24×7). r6id.xlarge pairs 4 vCPUs with 32GB at $0.3024/hr (~$218/mo). r6id.large is 100% cheaper per hour than r6id.xlarge ($0.1512/hr gap).

Because both instances are in the **r6id family**, the only thing that changes between them is sizing — same silicon, same architecture (Intel Xeon (x86_64)), same burstable/sustained behavior. The choice is purely about how much capacity you actually need: r6id.large gives you 2 vCPUs and 16GB of RAM, r6id.xlarge gives you 4 vCPUs and 32GB. AWS scales pricing close to linearly within a family, so picking the right size is mostly about right-sizing your workload, not getting a better deal per vCPU.

On raw price-per-performance, the two are r6id.large delivers ~100% more single-thread Sysbench score per dollar (19636 vs 9838 points per $1/hr). That's the cleanest signal we have for "which one runs your workload faster per dollar," but it only matters if your workload is single-thread-bound; for parallel workloads the multi-core scores (3067 vs 6160) are what to weigh. Spot pricing flips many of these comparisons — when r6id.large drops to $0.0456/hr and r6id.xlarge drops to $0.1404/hr, the cheap-per-hour winner can swing meaningfully.

In practice, pick r6id.large when your workload is closer to memory-optimized (memory-bound work — in-memory databases, real-time analytics, large caches). Pick r6id.xlarge when it's closer to memory-optimized (memory-bound work — in-memory databases, real-time analytics, large caches). When neither side is obviously right, the cheaper hourly rate usually wins for fault-tolerant batch workloads, while the higher single-core score usually wins for latency-sensitive web traffic. The regional pricing tables linked from each instance page below show where each is currently cheapest — sometimes a >20% regional gap flips the comparison entirely.