WordpressによりCPU使用率が高くなります（mysqld）
私は、debian専用サーバーで実行されているMYSQLデータベースに500-kの投稿があるwordpressサイトを持っています。
サーバーOS：Debian 8 "Jesssie）"-Linuxバージョン4.9.58-xxxx-std-ipv6-64（[email protected]）（gccバージョン6.3.0 20170516（Debian 6.3。 0-18））＃1 SMP 10月23日11:35:59 CEST 2017（Ispconfig）
Webサーバー：サーバーのバージョン：Apache/2.4.10（Debian）
[〜＃〜] php [〜＃〜]：PHPバージョン7.1.8
プロセッサ：Intel 2x Xeon E5-2630v3-16/32t-2.4GHz /3.2GHz
[〜＃〜] ram [〜＃〜]：128GB DDR4 ECC 1866 MHz
ディスク：SoftRaid 2x450GB SSD NVMe
今日、MySQLが高いCPU使用率を引き起こしていることに気づきました。
2383 mysql 20 0 68.666g 7.596g 11152 S 2435％ 6.0 108：43.00 mysqld
top：
top - 18:05:42 up 6 min, 1 user, load average: 23.29, 14.22, 6.09
Tasks: 548 total, 4 running, 544 sleeping, 0 stopped, 0 zombie
%Cpu0 : 25.8 us, 61.0 sy, 0.0 ni, 13.2 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu1 : 25.2 us, 57.7 sy, 0.0 ni, 17.1 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu2 : 24.7 us, 49.3 sy, 0.0 ni, 26.0 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu3 : 53.6 us, 15.9 sy, 0.0 ni, 30.5 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu4 : 27.0 us, 43.0 sy, 0.0 ni, 30.0 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu5 : 24.8 us, 41.3 sy, 0.0 ni, 33.9 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu6 : 59.3 us, 31.8 sy, 0.0 ni, 8.9 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu7 : 21.6 us, 63.2 sy, 0.0 ni, 15.2 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu8 : 41.5 us, 40.5 sy, 0.0 ni, 18.1 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu9 : 51.5 us, 35.6 sy, 0.0 ni, 12.5 id, 0.3 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu10 : 41.0 us, 39.2 sy, 0.0 ni, 19.8 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu11 : 55.4 us, 33.2 sy, 0.0 ni, 11.4 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu12 : 76.9 us, 10.0 sy, 0.0 ni, 13.0 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu13 : 81.7 us, 3.0 sy, 0.0 ni, 15.3 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu14 : 31.8 us, 43.2 sy, 0.0 ni, 25.0 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu15 : 35.3 us, 58.7 sy, 0.0 ni, 6.0 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu16 : 24.4 us, 52.5 sy, 0.0 ni, 23.1 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu17 : 26.0 us, 64.3 sy, 0.0 ni, 9.7 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu18 : 34.9 us, 36.6 sy, 0.0 ni, 28.5 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu19 : 20.0 us, 46.7 sy, 0.0 ni, 33.3 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu20 : 86.3 us, 1.0 sy, 0.0 ni, 12.7 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu21 : 36.2 us, 51.2 sy, 0.0 ni, 12.6 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu22 : 25.5 us, 46.0 sy, 0.0 ni, 28.5 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu23 : 19.7 us, 41.5 sy, 0.0 ni, 38.8 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu24 : 62.3 us, 4.6 sy, 0.0 ni, 33.1 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu25 : 26.3 us, 60.9 sy, 0.0 ni, 12.8 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu26 : 57.3 us, 24.7 sy, 0.0 ni, 18.0 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu27 : 73.6 us, 7.9 sy, 0.0 ni, 18.5 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu28 : 21.7 us, 42.8 sy, 0.0 ni, 35.1 id, 0.0 wa, 0.0 hi, 0.3 si, 0.0 st
%Cpu29 : 43.3 us, 37.0 sy, 0.0 ni, 19.7 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu30 : 26.2 us, 57.8 sy, 0.0 ni, 15.9 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
%Cpu31 : 28.2 us, 65.8 sy, 0.0 ni, 5.7 id, 0.0 wa, 0.0 hi, 0.3 si, 0.0 st
KiB Mem: 13198007+total, 16391500 used, 11558857+free, 86084 buffers
KiB Swap: 1046520 total, 0 used, 1046520 free. 5456440 cached Mem
プロセスリスト全体を表示;
mysql> show full processlist;
+------+---------------+-----------+---------------+---------+------+----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Id | User | Host | db | Command | Time | State | Info |
+------+---------------+-----------+---------------+---------+------+----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| 1541 | root | localhost | NULL | Query | 0 | NULL | show full processlist |
| 1604 | c1database | localhost | c1database | Query | 2 | Sending data | SELECT post_id FROM wp_postmeta WHERE meta_key = '_wp_attached_file' AND meta_value = '2018/01/amp.jpg' |
| 1605 | c1database | localhost | c1database | Query | 1 | Sending data | SELECT post_id FROM wp_postmeta WHERE meta_key = '_wp_attached_file' AND meta_value = '2018/01/amp.jpg' |
| 1610 | c1database | localhost | c1database | Query | 0 | Sorting result | SELECT t.*, tt.* FROM wp_terms AS t INNER JOIN wp_term_taxonomy AS tt ON t.term_id = tt.term_id WHERE tt.taxonomy IN ('post_tag') AND tt.count > 0 ORDER BY tt.count DESC LIMIT 45 |
| 1611 | c1database | localhost | c1database | Query | 6 | Sorting result | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1613 | c1database | localhost | c1database | Query | 5 | Sorting result | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1614 | c1database | localhost | c1database | Query | 4 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1615 | c1database | localhost | c1database | Query | 3 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1616 | c1database | localhost | c1database | Query | 3 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1617 | c1database | localhost | c1database | Query | 2 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1618 | c1database | localhost | c1database | Query | 2 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1619 | c1database | localhost | c1database | Query | 2 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1620 | c1database | localhost | c1database | Query | 2 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1621 | c1database | localhost | c1database | Query | 2 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1622 | c1database | localhost | c1database | Query | 2 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1623 | c1database | localhost | c1database | Query | 1 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1624 | c1database | localhost | c1database | Query | 1 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1625 | c1database | localhost | c1database | Query | 1 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1626 | c1database | localhost | c1database | Query | 1 | Sending data | SELECT post_id FROM wp_postmeta WHERE meta_key = '_wp_attached_file' AND meta_value = '2018/01/amp.jpg' |
| 1627 | c1database | localhost | c1database | Query | 1 | Sending data | SELECT post_id FROM wp_postmeta WHERE meta_key = '_wp_attached_file' AND meta_value = '2018/01/amp.jpg' |
| 1628 | c1database | localhost | c1database | Query | 1 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1629 | c1database | localhost | c1database | Query | 1 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1630 | c1database | localhost | c1database | Query | 0 | Copying to tmp table | SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts WHERE 1=1 AND wp_posts.post_type = 'post' AND (wp_posts.post_status = 'publish') ORDER BY Rand() LIMIT 0, 10 |
| 1631 | c1database | localhost | c1database | Query | 0 | Sending data | SELECT post_id FROM wp_postmeta WHERE meta_key = '_wp_attached_file' AND meta_value = '2018/01/amp.jpg' |
| 1632 | c1database | localhost | c1database | Query | 0 | Sending data | SELECT post_id FROM wp_postmeta WHERE meta_key = '_wp_attached_file' AND meta_value = '2018/01/amp.jpg' |
+------+---------------+-----------+---------------+---------+------+----------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
25 rows in set (0.00 sec)
mysql>
my.cnf（MySQL）：
innodb_buffer_pool_size = 61440M
innodb_file_per_table=1
innodb_log_file_size = 1024M
innodb_buffer_pool_instances=60
key_buffer = 2048M
max_allowed_packet = 16M
thread_stack = 192K
thread_cache_size = 8
# This replaces the startup script and checks MyISAM tables if needed
# the first time they are touched
myisam-recover = BACKUP
#max_connections = 100
#table_cache = 64
#thread_concurrency = 10
#
# * Query Cache Configuration
#
query_cache_limit = 1M
query_cache_size = 0
query_cache_type = 0
#query_cache_size = 8192M
25クエリ MySQLで2435％CPU使用率が生成されました。何かアドバイス？ありがとうございました！
CPU使用率が高いかクエリが遅い-クエリやインデックス、デザインを修正する必要があります。
Wp_postmetaのスキーマは設計が不十分です。それを改善する方法については、 ここ のヒントを参照してください。
テーブルはENGINE = MyISAMですか？またはENGINE = InnoDB？ 128GBのRAMをより有効に活用するためにmy.cnfに加える1つの変更については、 this を参照してください。おそらく十分に活用されていません。
上記の変更後でも、いくつかの厄介なクエリがある可能性があります。 それらを見つける なので、（別の質問で）それらを高速化する方法について話し合うことができます。