The open-source database community is excited to announce the release of MySQLTuner v2.9.2, a major maintenance and feature release. This version introduces key auditing features for distributed database environments and resolves critical hardware and software detection bugs.
1. Major New Features
A. Advanced Galera Cluster Diagnostics (wsrep)
Multi-source sync replication architectures using Galera (such as Percona XtraDB Cluster or MariaDB Galera) now benefit from deep network and lock auditing:
* Network & Disk Latency: Monitors wsrep_local_recv_queue_avg and wsrep_local_send_queue_avg. High values suggest write-cache bottlenecks on storage arrays or slow network pipes.
* Primary Key Certification Conflicts: Evaluates wsrep_cert_deps_failed to count transactions aborted due to key collisions across multi-node setups.
* Quorum & Split-Brain Detection: Alerts if wsrep_cluster_status is not Primary, pointing to lost quorum and isolated nodes.
Example output alerts generated by MySQLTuner:
[!!] Galera cluster is in non-Primary state (Quorum lost): wsrep_cluster_status = non-Primary
[!!] High certification failures detected: wsrep_cert_deps_failed = 1420 (Check multi-master write workload)
B. Enhanced InnoDB Cluster & Group Replication
Auditing MySQL 8.x Group Replication topologies has been hardened:
* Better evaluation of Consensus engine variables (such as group_replication_primary_member).
* Correlates system memory against replication message cache configurations.
2. Speed Optimization: The --skipworkload CLI Parameter
On high-concurrency servers processing thousands of Queries Per Second (QPS), computing schema statistics (like auto-increment usage or table fragmentation) might add unintended overhead.
The new --skipworkload option allows DBAs to bypass these checks:
# Execute audit while skipping workload profiling
./mysqltuner.pl --skipworkload
By skipping workload checks, the database query overhead from the script is reduced by over 60%. Additionally, the remaining auto-increment exhaustion check has been optimized by fetching COLUMN_TYPE directly in the initial query on INFORMATION_SCHEMA.
3. Bugfixes & HW Controller Mapping
- LSI/AVAGO MegaRAID Support: Fixed regex parsing for utility binaries (
MegaCliandstorcli). It now correctly validates write-cache modes (WriteBackvsWriteThrough) in relation to the battery backup unit (BBU) or SuperCap status. - Write-Back: Data is written to the controller cache, allowing immediate acknowledgement (fast, safe with a BBU).
- Write-Through: Data is written directly to physical drives (slow, fallback mode when BBU is absent or failed).
[!!] RAID controller write-cache is set to WriteThrough (Data safety warning: No BBU/SuperCap detected!)
- Downstream CVE Fallback: If the local script directory lacks
vulnerabilities.csv, it falls back to the system packaging folder/usr/share/mysqltuner/vulnerabilities.csv(Debian/Ubuntu compliant).
Getting Started with v2.9.2
Upgrade your local script now:
wget http://mysqltuner.pl/ -O mysqltuner.pl
chmod +x mysqltuner.pl
./mysqltuner.pl