MySQL 8.0 Configuration Advisor

Offline sizing and memory risk estimator

Size MySQL safely before editing my.cnf

Enter server capacity and workload characteristics. The advisor separates global memory, connected-session baseline, active-query buffers, temporary-table exposure, and OS reserve.

Memory summary

Expected peak scenario

Safe
Total RAM — Physical capacity
Expected peak — —
Safety margin — —
Safe connections — Approximate heavy-workload limit

RAM allocation visualisation

Switch between idle, typical, peak, and conservative planning scenarios.

— of RAM used
Capacity used vs. physical RAM 80% caution  92% high risk
Scenario usage——
Remaining RAM—After estimated usage
Per extra active session—Estimated incremental exposure
Potential exposure——

Dynamic warnings

These change as hardware, concurrency, and parameter values change.

Connection what-if analysis

Drag the slider to see how higher connection limits affect potential memory exposure.

150
Recommended safe—Conservative target
Typical-workload limit—Approximate
Heavy-workload limit—Approximate
What-if upper exposure——

Memory growth by connection count

Estimated memory as concurrency rises, from typical to heavy workload.

Heavy workload Typical workload Likely range Physical RAM

Scenario comparison

All four planning scenarios side by side against physical RAM.

Recommended parameters

Edit values, lock selected rows, and observe the live memory model.

Parameter Recommended Your value Scope Status Reason Lock Reset

Generated my.cnf

Only the parameters shown by this advisor are exported.

Apply without editing files

Run these from a client with SUPER / SYSTEM_VARIABLES_ADMIN.

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Calculation transparency

Review the formulas and terminology used by the estimator.

How this was calculated
Important interpretation notes

Global allocations such as the InnoDB buffer pool are treated separately from connection and query buffers. Per-session settings are modelled using expected active concurrency, because they are not all guaranteed to be allocated for every connected session at the same time.

innodb_redo_log_capacity is storage capacity, not normal resident RAM, so it is not added to the RAM bar.

Glossary
Global memoryServer-wide allocations shared by sessions.
Per-session bufferMemory that may be allocated for one connection or operation.
Active connectionA session currently executing work.
Maximum connectionThe configured ceiling, not the number always active.
Potential exposureA cautious planning estimate, not guaranteed resident memory.
Safety marginRAM remaining after the selected scenario.
Buffer poolInnoDB cache for data and indexes.
Temporary tableIntermediate result storage that may consume RAM.