Performance Optimization
MySQL Slow Query Analysis
Nine slow sites out of ten are slow databases wearing a website costume. Systematic slow-query analysis, logging, aggregation by total impact, EXPLAIN plans, and index design, converts mystery slowness into a ranked fix list with measured wins after every change.
Key points
- Enable slow-query and no-index logging with sane long_query_time thresholds.
- Aggregate with pt-query-digest: rank by total time, not single worst queries.
- Read EXPLAIN output properly: access type, key usage, rows examined vs sent.
- Design covering indexes for hot paths; remove overlapping redundant ones.
- Fix N+1 patterns in application code, no index saves chatty loops.
- Right-size tmp_table, join buffers, and InnoDB pool from evidence.
- Re-measure top queries after each change; keep a query performance log.
- Schedule recurring analysis, data growth silently invalidates old plans.
Field note
Rank by total time, not worst single query. The query that runs 40,000 times a day at 200ms costs forty times more than the dramatic one that runs nightly.
Frequently asked questions
Why is the site slow when CPU is idle?
Classic database wait, queries queue while CPUs idle. Slow logs prove it in minutes.
How much improvement is typical?
10-100x on fixed queries is routine; whole-site 2-5x after a full pass is common.
Will analysis disrupt production?
Logging overhead is ~1%; analysis happens off-production on log copies.
What about Percona or MariaDB?
Same methodology, engine-aware details, we tune MySQL, MariaDB, and Percona Server.
How Kinetikatech helps with performance optimization
This is what we do every day: Server tuning, database optimization, caching, and front-end speed work that cuts load times and hosting costs. Our Website Speed Optimization and Server Management service covers it end to end, assessment, implementation, 24/7 monitoring, and emergency response within 30 minutes.