我们的网站为我们的用户端报告功能运行了一些相当大的收入查询。较大的帐户在某些页面上加载需要 5-20 秒。当这些查询运行时，他们正在使用 MYSQL SUM() 函数计算收益，我相信这会创建大量临时表，并且看起来有些正在磁盘上创建。我一直在运行 MYSQL Tuner，但它不再对我的设置进行任何可变调整。这是一个示例输出：
-------- Performance Metrics -------------------------------------------------
[--] Up for: 5h 14m 29s (1M q [98.277 qps], 143K conn, TX: 2B, RX: 212M)
[--] Reads / Writes: 94% / 6%
[--] Total buffers: 4.1G global + 3.8M per thread (600 max threads)
[!!] Maximum possible memory usage: 6.3G (89% of installed RAM)
[OK] Slow queries: 0% (7K/1M)
[OK] Highest usage of available connections: 2% (14/600)
[OK] Key buffer size / total MyISAM indexes: 640.0M/1.0G
[OK] Key buffer hit rate: 99.9% (237M cached / 135K reads)
[OK] Query cache efficiency: 62.5% (756K cached / 1M selects)
[OK] Query cache prunes per day: 0
[OK] Sorts requiring temporary tables: 0% (429 temp sorts / 134K sorts)
[OK] Temporary tables created on disk: 21% (25K on disk / 120K total)
[OK] Thread cache hit rate: 99% (14 created / 143K connections)
[OK] Table cache hit rate: 70% (247 open / 348 opened)
[OK] Open file limit used: 0% (440/760K)
[OK] Table locks acquired immediately: 99% (577K immediate / 578K locks)
[OK] InnoDB data size / buffer pool: 144.0K/8.0M
-------- Recommendations -----------------------------------------------------
General recommendations:
Run OPTIMIZE TABLE to defragment tables for better performance
MySQL started within last 24 hours - recommendations may be inaccurate
Reduce your overall MySQL memory footprint for system stability
这也是我的 MY.CNF 设置：
[mysqld]
safe-show-database
skip-locking
skip-networking
max_connections = 600
key_buffer = 640M
table_cache = 380000
query_cache_size = 1024M
query_cache_limit = 12M
query_cache_type = 1
local-infile=0
long_query_time=1
myisam_sort_buffer_size = 64M
max_heap_table_size = 2560M
tmp_table_size = 2560M
max_allowed_packet = 8M
thread_cache_size = 70
thread_stack = 256K
sort_buffer_size = 512K
read_buffer_size = 512K
read_rnd_buffer_size = 512K
binlog_cache_size=64K
long_query_time=1
log-slow-queries=/var/log/slow-query.log
low_priority_updates=1
concurrent_insert=2
log-queries-not-using-indexes
join_buffer_size=2M
thread_concurrency = 16
任何帮助，将不胜感激。我需要让这些页面加载得更快。该服务器是具有 8 GB RAM 的四核 x2（8 CPU）。这些表是完全索引的。谢谢。
**已解决：我能够通过为 WHERE 列创建多列索引来解决此问题。看起来这与在磁盘上创建的临时表造成的缓慢无关。QPS 从 98 跃升至 212。