我們有一個運行 Magento 的 ec2 m2.4xlarge（centos 5.6、httpd 2.2、php 5.2.17 和 eaccelerator 0.9.5.3、mysql 5.1.52）。現在我們的流量激增，我們的頂部如下所示：
top - 09:41:29 up 31 days, 1:12, 1 user, load average: 120.01, 129.03, 113.23
Tasks: 1190 total, 18 running, 1172 sleeping, 0 stopped, 0 zombie
Cpu(s): 97.3%us, 1.8%sy, 0.0%ni, 0.5%id, 0.0%wa, 0.0%hi, 0.0%si, 0.4%st
Mem: 71687720k total, 36898928k used, 34788792k free, 49692k buffers
Swap: 880737784k total, 0k used, 880737784k free, 1586524k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
2433 mysql 15 0 23.6g 4.5g 7112 S 564.7 6.6 33607:34 mysqld
24046 apache 16 0 411m 65m 28m S 26.4 0.1 0:09.05 httpd
24360 apache 15 0 410m 60m 25m S 26.4 0.1 0:03.65 httpd
24993 apache 16 0 410m 57m 21m S 26.1 0.1 0:01.41 httpd
24838 apache 16 0 428m 74m 20m S 24.8 0.1 0:02.37 httpd
24359 apache 16 0 411m 62m 26m R 22.3 0.1 0:08.12 httpd
23850 apache 15 0 411m 64m 27m S 16.8 0.1 0:14.54 httpd
25229 apache 16 0 404m 46m 17m R 10.2 0.1 0:00.71 httpd
14594 apache 15 0 404m 63m 34m S 8.4 0.1 1:10.26 httpd
24955 apache 16 0 404m 50m 21m R 8.4 0.1 0:01.66 httpd
24313 apache 16 0 399m 46m 22m R 8.1 0.1 0:02.30 httpd
25119 apache 16 0 411m 59m 23m S 6.8 0.1 0:01.45 httpd
問題：
- 為 msyqld 提供更多記憶體是否有助於它快取查詢並更快地做出反應？
- 如果是這樣，怎麼辦？
- 除了將 mysql 和 php 拆分到單獨的伺服器（我們即將要做的）之外，我們還可以/應該做什麼？
謝謝！
更新:
這是我們的 my.cnf 以及 mysqltuner 的輸出。看起來像是快取問題。再次感謝！
# cat /etc/my.cnf
[client]
port = ****
socket = /var/lib/mysql/mysql.sock
[mysqld]
datadir=/mnt/persistent/mysql
port=****
socket=/var/lib/mysql/mysql.sock
key_buffer = 512M
max_allowed_packet = 64M
table_cache = 1024
sort_buffer_size = 8M
read_buffer_size = 4M
read_rnd_buffer_size = 2M
myisam_sort_buffer_size = 64M
thread_cache_size = 128M
tmp_table_size = 128M
join_buffer_size = 1M
query_cache_limit = 2M
query_cache_size= 64M
query_cache_type = 1
max_connections = 1000
thread_stack = 128K
thread_concurrency = 48
log-bin=mysql-bin
server-id = 1
wait_timeout = 300
innodb_data_home_dir = /mnt/persistent/mysql/
innodb_data_file_path = ibdata1:10M:autoextend
innodb_buffer_pool_size = 20G
innodb_additional_mem_pool_size = 20M
innodb_log_file_size = 64M
innodb_log_buffer_size = 8M
innodb_flush_log_at_trx_commit = 1
innodb_lock_wait_timeout = 50
innodb_thread_concurrency = 48
ft_min_word_len=3
[myisamchk]
ft_min_word_len=3
key_buffer = 128M
sort_buffer_size = 128M
read_buffer = 2M
write_buffer = 2M
# ./mysqltuner.pl
>> MySQLTuner 1.2.0 - Major Hayden <[email protected]>
>> Bug reports, feature requests, and downloads at http://mysqltuner.com/
>> Run with '--help' for additional options and output filtering
-------- General Statistics --------------------------------------------------
[--] Skipped version check for MySQLTuner script
[OK] Currently running supported MySQL version 5.1.52-log
[OK] Operating on 64-bit architecture
-------- Storage Engine Statistics -------------------------------------------
[--] Status: +Archive -BDB +Federated +InnoDB -ISAM -NDBCluster
[--] Data in MyISAM tables: 2G (Tables: 26)
[--] Data in InnoDB tables: 749M (Tables: 250)
[!!] Total fragmented tables: 262
-------- Security Recommendations -------------------------------------------
-------- Performance Metrics -------------------------------------------------
[--] Up for: 31d 2h 30m 38s (680M q [253.371 qps], 2M conn, TX: 4825B, RX: 236B)
[--] Reads / Writes: 89% / 11%
[--] Total buffers: 20.6G global + 15.1M per thread (1000 max threads)
[OK] Maximum possible memory usage: 35.4G (51% of installed RAM)
[OK] Slow queries: 0% (35K/680M)
[OK] Highest usage of available connections: 53% (537/1000)
[OK] Key buffer size / total MyISAM indexes: 512.0M/457.2M
[OK] Key buffer hit rate: 100.0% (9B cached / 264K reads)
[OK] Query cache efficiency: 42.3% (260M cached / 615M selects)
[!!] Query cache prunes per day: 4384652
[OK] Sorts requiring temporary tables: 0% (1K temp sorts / 38M sorts)
[!!] Joins performed without indexes: 100404
[OK] Temporary tables created on disk: 17% (7M on disk / 45M total)
[OK] Thread cache hit rate: 99% (537 created / 2M connections)
[!!] Table cache hit rate: 0% (1K open / 946K opened)
[OK] Open file limit used: 9% (453/5K)
[OK] Table locks acquired immediately: 99% (758M immediate / 758M locks)
[OK] InnoDB data size / buffer pool: 749.3M/20.0G
-------- Recommendations -----------------------------------------------------
General recommendations:
Run OPTIMIZE TABLE to defragment tables for better performance
Enable the slow query log to troubleshoot bad queries
Adjust your join queries to always utilize indexes
Increase table_cache gradually to avoid file descriptor limits
Variables to adjust:
query_cache_size (> 64M)
join_buffer_size (> 1.0M, or always use indexes with joins)
table_cache (> 1024)
答案1
Would giving msyqld more memory help it cache queries and react faster?
你可以給 MySQL 更多的表緩存，這會有所幫助，但我不認為這對你來說不是一個太大的問題。由於 MySQL 進程的 CPU 使用率非常高，我相信這只是所有連線減慢 MySQL 速度的原因。
我喜歡用來調整 MySQL 的一個不錯的網站是 MySQL 記憶體計算器： http://www.omh.cc/mycnf/
我還建議您查看 GitHub 上的以下 Perl 腳本，因為它將檢查您的整個 MySQL 配置是否有任何錯誤。 http://mysqltuner.com
最後，我相信對您的情況有所幫助的是一些 HTTP 快取。如果您的網站非常動態（您的網站似乎是這樣，因為資料庫 CPU 使用率和記憶體相當高），那麼擁有一些 HTTP 快取將減輕 MySQL 的一些負載。我個人使用 Varnish（因為我現在不能發布兩個以上的超鏈接，你可以透過簡單的 Google 搜尋找到它），但還有其他的。
希望有幫助。我不像這裡的一些用戶那樣天才，但希望這些提示能有所幫助。
答案2
您可以在 Apache 前面使用 Nginx。這將使 Nginx 代表客戶端向 Apache 發出代理請求，您也可以將壓縮卸載到 Apache。如果您這樣做，請嘗試將最大 Apache 進程數減少到不會降低伺服器速度的程度。
您也可以設定 Nginx 來提供靜態內容而不是 Apache。
此連結可以幫助您入門。
http://tumblr.intranation.com/post/766288369/using-nginx-reverse-proxy