AWS bill line item
Aurora:StorageIOUsage
The per-operation charge for read and write I/O requests against Aurora's distributed storage layer, under the default storage configuration.
Aurora I/O requests
Verified against official AWS documentation last checked
Why it shows up
Every database page read that isn't served from the buffer cache, and every write, counts as a billed I/O operation. Write-heavy workloads, cold caches after a failover or restart, or queries doing large scans generate outsized I/O charges relative to their compute footprint.
This is the exact line item Aurora's I/O-Optimized storage configuration is designed to eliminate: switching configurations removes all per-I/O charges in exchange for a higher storage-GB rate, which can meaningfully cut total Aurora cost once I/O is a large share of Aurora spend.
How to cut it
- Check what share of total Aurora spend this line represents; a large share favors switching to the I/O-Optimized configuration.
- Increase buffer pool cache hit ratio by right-sizing instance memory or tuning working-set size.
- Reduce unnecessary full table scans and optimize indexes to cut read I/O.
- Batch writes where possible to reduce the number of billed write operations.
How to read a usage type
The colon in Aurora:StorageIOUsage doesn't introduce an instance type the way it does in a code like BoxUsage:m5.large. This code carries no region or direction token either, so there's nothing to break down here.
Source
Source: AWS docs →Found Aurora:StorageIOUsage on your own bill?
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