AWS RDS PostgreSQL shared_buffers

aws_rds_postgres shared_buffers.md

Source: https://stackoverflow.com/questions/42478488/resize-shared-buffer-size-in-postgresql-hosted-in-aws-rds

To calculate the correct value for shared_buffers in a AWS RDS PostgreSQl database:

(2*1024*1024*12.5/100)/8)
# = 32768

The values:

• 2*1024*1024
  • DB instance has 2 [GB] of RAM.
  • 1024*1024 converts GB to kB.
• 12.5/100
  • 12.5 [%] of the RAM should be assigned to shared_buffers.
• /8
  • Postgres works with blocks of 8 [kB] size.

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So, if you would like to increase the value for shared_buffers to 25 [%] (instead of 12.5 [%]), you would want to have:

(2*1024*1024*25/100)/8)
# = 65536