What version of PostgreSQL? What instance type?
Have you tried Performance Insights?
Turns out our T2 instance had ran out of CPU credits, but this fact only became apparent after digging into CloudWatch metrics. It would be great if that info was displayed in the regular monitoring (as is the case for EC2 instances).
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RDS Postgresql migrate to Aurora Postgresql. Not showing "Aurora read replica" & "Migrate snapshot" options.Accepted Answerasked 9 months ago
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[Announcement]: Amazon RDS for PostgreSQL 10 deprecationasked 24 days ago
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Amazon RDS for PostgreSQL: Configuration differences with PostgreSQL on EC2Accepted Answerasked 2 years ago
RDS Read IOPS, Read Throughput, Queue Depth sudden increaseasked 8 months ago
RDS instance stuck in "Configuring-enhanced-monitoring" state for weeksasked 8 months ago
Migrating RDS PostgreSQL to Aurora PostgreSQL in a different accountAccepted AnswerEXPERTasked 2 years ago