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You can also consider setting innodb_flush_log_at_trx_commit = 2. The default setting of 1 is required for full ACID compliance and logs are written and flushed to disk at each transaction commit. However, this can be expensive in terms of disk I/O. With a setting of 2, logs are written after each transaction commit and flushed to disk once per second. Transactions for which logs have not been flushed can be lost in a crash. The tradeoff here may be acceptable in your environment.
For those running MariaDB you should read this knowledge base article about OPTIMIZE and defragmenting. Some have found MariaDB 10.3+ to be a good, fast variant of MySQL for use by Grouper.
Database Whitelists and Blacklists
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