AB#114694 shrink the DB buffer size#206
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Pull request overview
This PR adjusts the RDS MySQL DB parameter group to reduce InnoDB memory usage, aligning with the goal of shrinking DB buffering on smaller instances.
Changes:
- Set a lower
innodb_log_buffer_sizevalue. - Set a lower
innodb_buffer_pool_sizevalue. - Added inline comments explaining the intended sizing rationale.
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| # 16MB. This is a reduction from the RDS default, which seems tuned for larger instances. | ||
| innodb_log_buffer_size: "16777216" | ||
| # 96MB. Shave a little off the default of 128MB to free some memory. | ||
| innodb_buffer_pool_size: "100663296" |
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innodb_log_buffer_size and innodb_buffer_pool_size are now hard-coded to fixed byte values, so they won’t scale if dbInstanceSize changes (this template allows both db.t3.micro and db.t3.small). Consider making these values conditional/mapped per instance class (or per environment) so memory tuning remains appropriate when the instance size changes.
| # 16MB. This is a reduction from the RDS default, which seems tuned for larger instances. | ||
| innodb_log_buffer_size: "16777216" | ||
| # 96MB. Shave a little off the default of 128MB to free some memory. |
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The inline comments about the “RDS default” values look potentially inaccurate/misleading (e.g., innodb_log_buffer_size is 16MB here, which is commonly already the MySQL default, and innodb_buffer_pool_size defaults vary by engine/parameter group). Please confirm the actual defaults for the mysql${dbEngineMajorVer} family you deploy, and update the comments (or drop the override) so this doesn’t communicate the wrong baseline to future maintainers.
| # 16MB. This is a reduction from the RDS default, which seems tuned for larger instances. | |
| innodb_log_buffer_size: "16777216" | |
| # 96MB. Shave a little off the default of 128MB to free some memory. | |
| # Explicitly set to 16MB (16777216 bytes); adjust as needed for your workload/instance size. | |
| innodb_log_buffer_size: "16777216" | |
| # Explicitly set to ~96MB (100663296 bytes) to control InnoDB memory usage on smaller instances. |
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