# AWS study finds PostgreSQL prewarming cuts restore delays > AWS compared Amazon RDS for PostgreSQL instances restored from the same snapshot. One 1,200-GiB database on gp3 was prewarmed with 15 parallel pg_prewarm sessions; another hydrated passively. The first instance completed storage initialization in about five hours. - Canonical URL: https://newsverum.com/en/news/aws-rds-postgresql-snapshot-restore-prewarming-test - Publisher: Newsverum - Section: Technology - Published: 2026-10-15T21:30:20+00:00 - Updated: 2026-10-15T21:30:20+00:00 - Event / data period: 2026-10-14 - Other editions: [Türkçe](https://newsverum.com/tr/news/aws-rds-postgresql-snapshot-restore-prewarming-test.md), [العربية](https://newsverum.com/ar/news/aws-rds-postgresql-snapshot-restore-prewarming-test.md), [Français](https://newsverum.com/fr/news/aws-rds-postgresql-snapshot-restore-prewarming-test.md), [Español](https://newsverum.com/es/news/aws-rds-postgresql-snapshot-restore-prewarming-test.md), [Deutsch](https://newsverum.com/de/news/aws-rds-postgresql-snapshot-restore-prewarming-test.md), [Português](https://newsverum.com/pt/news/aws-rds-postgresql-snapshot-restore-prewarming-test.md) AWS compared Amazon RDS for PostgreSQL instances restored from the same snapshot. One 1,200-GiB database on gp3 was prewarmed with 15 parallel pg_prewarm sessions; another hydrated passively. The first instance completed storage initialization in about five hours. Both instances used db.m5.4xlarge with gp3 storage configured at 20,000 IOPS and 600 MiB/s throughput. The passive instance had reached only 23% after five hours, with completion estimated beyond 24 hours. In later tests, a large table scan took 44 seconds on the prewarmed instance and 571 on the other; a complex join took 123 and 1,531 seconds. AWS says results are specific to its test configuration. ## Data ### AWS study finds PostgreSQL prewarming cuts restore delays AWS compared Amazon RDS for PostgreSQL instances restored from the same snapshot. One 1,200-GiB database on gp3 was prewarmed with 15 parallel pg_prewarm sessions; another hydrated passively. The first instance completed storage initialization in about five hours. Both instances used db.m5.4xlarge with gp3 storage configured at 20,000 IOPS and 600 MiB/s throughput. The passive instance had reached only 23% after five hours, with completion estimated beyond 24 hours. In later tests, a large table scan took 44 seconds on the prewarmed instance and 571 on the other; a complex join took 123 and 1,531 seconds. AWS says results are specific to its test configuration. Methodology: Reported values and benefits are attributed to the source; no independent measurement was made. | date | label | description | status | |---|---|---|---| | 2026-10-14 | AWS study finds PostgreSQL prewarming cuts restore delays | AWS compared Amazon RDS for PostgreSQL instances restored from the same snapshot. One 1,200-GiB database on gp3 was prewarmed with 15 parallel pg_prewarm sessions; another hydrated passively. The first instance completed storage initialization in about five hours. Both instances used db.m5.4xlarge with gp3 storage configured at 20,000 IOPS and 600 MiB/s throughput. The passive instance had reached only 23% after five hours, with completion estimated beyond 24 hours. In later tests, a large table scan took 44 seconds on the prewarmed instance and 571 on the other; a complex join took 123 and 1,531 seconds. AWS says results are specific to its test configuration. | occurred | Sources: · Download data: [JSON](https://newsverum.com/api/v1/articles/aws-rds-postgresql-snapshot-restore-prewarming-test/data/source-report?lang=en&format=json) · [CSV](https://newsverum.com/api/v1/articles/aws-rds-postgresql-snapshot-restore-prewarming-test/data/source-report?lang=en&format=csv) ## Sources - [AWS Database Blog]() (Source checked: 2026-10-15; Published: 2026-10-14) --- Cite the canonical URL above. [Editorial standards and corrections](https://newsverum.com/en/editorial)