| Component | datadb-c | datadb-d | Combined |
|---|---|---|---|
| EC2 compute | $1,064 | $1,029 | $2,094 |
| EBS volumes | $384 | $384 | $768 |
| Total | $1,448 | $1,413 | $2,862 |
The EC2 compute costs above are already post-savings-plan (effective) costs. The account has 4 active Compute Savings Plans (general-purpose, not locked to any instance family) with a combined commitment of ~$1,560/mo and ~100% utilization.
m6id coverage is ~91% — most of the datadb compute spend is covered by savings plans. Without them, the on-demand rate for m6id.4xlarge in ap-southeast-2 would be significantly higher. Since these are Compute Savings Plans, they'd automatically apply if the instances were changed to a different type.
Sampled 20% of layer tables (5,344 of ~26,700) to estimate LDS vs non-LDS disk usage:
| Category | Tables (sampled) | Size (sampled) | Estimated total |
|---|---|---|---|
| LDS | 1,173 | 397 GB | ~992 GB |
| non-LDS | 4,171 | 670 GB | ~1,675 GB |
| Total | 5,344 | 1,067 GB | ~2,666 GB |
LDS tables account for ~37% of datadb disk usage.
Current volume usage is ~2.7 TB per instance (91% of 3 TB). Removing ~1 TB of LDS data would reduce usage to ~1.7 TB, allowing volumes to be downsized from 3,000 GB to ~2,000 GB.
| 3,000 GB (current) | 2,000 GB (without LDS) | |
|---|---|---|
| Storage (gp3) | $316.80 | $211.20 |
| IOPS (10k) | $46.20 | $46.20 |
| Throughput (600 MB/s) | $25.08 | $25.08 |
| Per volume | $388.08 | $282.48 |
Savings: ~$211/mo ($2,534/yr) across both instances — only ~7% of the total $2,862/mo datadb cost. Compute dominates at $2,094/mo.
Removing LDS would significantly reduce query load, allowing downsizing from m6id.4xlarge. We don't need NVMe instance storage (data is on EBS), so switching to a non-d type is fine. For PostgreSQL, memory-optimized (r-series) is ideal since more RAM = more data cached in shared_buffers/OS page cache.
On-demand pricing in ap-southeast-2 (Compute Savings Plans apply automatically to all):
| Instance | vCPU | RAM | On-demand | ~Monthly (2 instances) |
|---|---|---|---|---|
| m6id.4xlarge (current) | 16 | 64 GB | $1.193/hr | $1,741 |
| r6i.2xlarge | 8 | 64 GB | $0.604/hr | $882 |
| r7i.2xlarge | 8 | 64 GB | $0.634/hr | $926 |
| r6i.xlarge | 4 | 32 GB | $0.302/hr | $441 |
| m6i.2xlarge | 8 | 32 GB | $0.480/hr | $701 |
Recommended: r6i.2xlarge — same 64 GB RAM as current, half the vCPUs (likely sufficient without LDS query load), ~49% cheaper on-demand. Savings Plans discount applies on top.
| Component | Current (2x m6id.4xlarge) | Downsized (2x r6i.2xlarge) | Savings |
|---|---|---|---|
| Compute | $2,094 | ~$1,047 | ~$1,047 |
| EBS volumes (3 TB → 2 TB) | $768 | ~$565 | ~$203 |
| Total | $2,862 | ~$1,612 | ~$1,250/mo ($15,000/yr) |