Помощь в оптимизации mysql

[OK] Maximum possible memory usage: 643.8M (64% of installed RAM)
[OK] Slow queries: 0% (1/3K)
[OK] Highest usage of available connections: 30% (9/30)
[OK] Key buffer size / total MyISAM indexes: 5.0M/4.2M
[OK] Key buffer hit rate: 97.6% (3K cached / 91 reads)
[OK] Query cache efficiency: 44.7% (1K cached / 2K selects)
[OK] Query cache prunes per day: 0
[OK] Sorts requiring temporary tables: 0% (2 temp sorts / 507 sorts)
[!!] Joins performed without indexes: 51
[OK] Temporary tables created on disk: 7% (56 on disk / 775 total)
[OK] Thread cache hit rate: 97% (9 created / 342 connections)
[OK] Table cache hit rate: 98% (534 open / 541 opened)
[OK] Open file limit used: 0% (102/30K)
[OK] Table locks acquired immediately: 100% (1K immediate / 1K locks)
[OK] InnoDB data size / buffer pool: 132.5M/500.0M