With a common multi-tenant policy (customer_id = current_setting('app.customer_id')::int), the same "latest 20 orders" query took 58 ms instead of 0.31 ms with an explicit WHERE clause, on a million rows with the right index in place. What we measured, why it happens, and how to write policies that keep their indexes.
A customer's 20 latest orders, 1 million rows, median (log scale). Our measurements, November 2026.
Row-level security is the standard way to isolate tenants in one Postgres database, and the way Supabase apps work. The full report shows the policy we used, the measurements, and the patterns that keep row-level security from turning index lookups into scans.
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Database Failover Downtime on AWS, Measured: RDS Multi-AZ 13–15 Seconds, Aurora Under 2
We wrote to Postgres every 50 ms and forced failovers. RDS Multi-AZ lost writes for 13.0 and 14.8 seconds; in one trial the switch began three minutes after the reboot was requested. Aurora PostgreSQL lost writes for 2.0 and 0.5 seconds, one failed write each time. The full timelines, the errors your application will see, and what to set so it recovers on its own.
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Aurora Serverless v2, Measured: 14–21 Seconds to Resume From Zero, Two Minutes to Scale to 16 ACUs
With auto-pause at 0 ACUs, the first query after a pause took 21.4 and 13.6 seconds to answer. Under sustained CPU load, the cluster went from 2 ACUs to its 16-ACU maximum in about two minutes, and tail latency fell from 24 seconds to 5. What that means for scale-to-zero databases behind real users.
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As of November 9, 2026. Provided as is, for general information, and accurate to the best of our knowledge on the date shown. Not legal, compliance, tax, financial or other professional advice. Prices, limits and vendor services change; check current vendor documentation before relying on anything here. Terms of use.