以下のすべてのクエリは、最大 2 分 20 秒かかる可能性がある開発サーバーで即座に実行されます。
クエリの実行時間は、ホームのあいまいな LIKE 文字列の影響を受けるようです。一致する国がほとんどない国と一致する場合は時間がかかりません。ドイツの場合は「ge」などを使用すると、実行に時間がかかります。しかし、これは常にそのようにうまくいくとは限りません。
データの送信が原因のようですが、その理由と意味は何ですか。また、本番環境のメモリはかなり少ないようです (空きメモリ)?
製品:
Intel Quad Xeon E3-1220 3.1GHz
4GB DDR3
2x 1TB SATA (RAID1)
ネットワーク速度 100Mb
Ubuntu
開発
Intel Core i3-2100、2C/4T、3.10GHz
500 GB SATA - RAID なし
4GB DDR3
このクエリは問題のクエリではありませんが、関連しているため、投稿してください。
SELECT
f.form_question_has_answer_id
FROM
form_question_has_answer f
INNER JOIN
project_company_has_user p ON f.form_question_has_answer_user_id = p.project_company_has_user_user_id
INNER JOIN
company c ON p.project_company_has_user_company_id = c.company_id
INNER JOIN
project p2 ON p.project_company_has_user_project_id = p2.project_id
INNER JOIN
user u ON p.project_company_has_user_user_id = u.user_id
INNER JOIN
form f2 ON p.project_company_has_user_project_id = f2.form_project_id
WHERE
(f2.form_template_name = 'custom' AND p.project_company_has_user_garbage_collection = 0 AND p.project_company_has_user_project_id = '29') AND (LCASE(c.company_country) LIKE '%ge%' OR LCASE(c.company_country) LIKE '%abcde%') AND f.form_question_has_answer_form_id = '174'
そして、上記のクエリの説明計画は、dev と production の両方で実行すると、同じ計画が生成されます。
+----+-------------+-------+--------+----------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+-------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+--------+----------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+-------------+
| 1 | SIMPLE | p2 | const | PRIMARY | PRIMARY | 4 | const | 1 | Using index |
| 1 | SIMPLE | f | ref | form_question_has_answer_form_id,form_question_has_answer_user_id | form_question_has_answer_form_id | 4 | const | 796 | Using where |
| 1 | SIMPLE | u | eq_ref | PRIMARY | PRIMARY | 4 | new_klarents.f.form_question_has_answer_user_id | 1 | Using index |
| 1 | SIMPLE | p | ref | project_company_has_user_unique_key,project_company_has_user_user_id,project_company_has_user_company_id,project_company_has_user_project_id | project_company_has_user_user_id | 4 | new_klarents.f.form_question_has_answer_user_id | 1 | Using where |
| 1 | SIMPLE | f2 | ref | form_project_id | form_project_id | 4 | const | 15 | Using where |
| 1 | SIMPLE | c | eq_ref | PRIMARY | PRIMARY | 4 | new_klarents.p.project_company_has_user_company_id | 1 | Using where |
+----+-------------+-------+--------+----------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+-------------+
このクエリの実行には 2 分 ~ 20 秒かかります。
サーバー上で実際に実行されているクエリは次のとおりです。
SELECT
COUNT(*) AS num_results
FROM (SELECT
f.form_question_has_answer_id
FROM
form_question_has_answer f
INNER JOIN
project_company_has_user p ON f.form_question_has_answer_user_id = p.project_company_has_user_user_id
INNER JOIN
company c ON p.project_company_has_user_company_id = c.company_id
INNER JOIN
project p2 ON p.project_company_has_user_project_id = p2.project_id
INNER JOIN
user u ON p.project_company_has_user_user_id = u.user_id
INNER JOIN
form f2 ON p.project_company_has_user_project_id = f2.form_project_id
WHERE
(f2.form_template_name = 'custom' AND p.project_company_has_user_garbage_collection = 0 AND p.project_company_has_user_project_id = '29') AND (LCASE(c.company_country) LIKE '%ge%' OR LCASE(c.company_country) LIKE '%abcde%') AND f.form_question_has_answer_form_id = '174'
GROUP BY
f.form_question_has_answer_id;) dctrn_count_query;
計画を説明する場合 (開発と本番で同じ):
+----+-------------+-------+--------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+------------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+--------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+------------------------------+
| 1 | PRIMARY | NULL | NULL | NULL | NULL | NULL | NULL | NULL | Select tables optimized away |
| 2 | DERIVED | p2 | const | PRIMARY | PRIMARY | 4 | | 1 | Using index |
| 2 | DERIVED | f | ref | form_question_has_answer_form_id,form_question_has_answer_user_id | form_question_has_answer_form_id | 4 | | 797 | Using where |
| 2 | DERIVED | p | ref | project_company_has_user_unique_key,project_company_has_user_user_id,project_company_has_user_company_id,project_company_has_user_project_id,project_company_has_user_garbage_collection | project_company_has_user_user_id | 4 | new_klarents.f.form_question_has_answer_user_id | 1 | Using where |
| 2 | DERIVED | f2 | ref | form_project_id | form_project_id | 4 | | 15 | Using where |
| 2 | DERIVED | c | eq_ref | PRIMARY | PRIMARY | 4 | new_klarents.p.project_company_has_user_company_id | 1 | Using where |
| 2 | DERIVED | u | eq_ref | PRIMARY | PRIMARY | 4 | new_klarents.p.project_company_has_user_user_id | 1 | Using where; Using index |
+----+-------------+-------+--------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------+---------+----------------------------------------------------+------+------------------------------+
本番サーバーで私が持っている情報は次のとおりです。
実行時:
+-------------+
| num_results |
+-------------+
| 3 |
+-------------+
1 row in set (2 min 14.28 sec)
プロフィールを表示:
+--------------------------------+------------+
| Status | Duration |
+--------------------------------+------------+
| starting | 0.000016 |
| checking query cache for query | 0.000057 |
| Opening tables | 0.004388 |
| System lock | 0.000003 |
| Table lock | 0.000036 |
| init | 0.000030 |
| optimizing | 0.000016 |
| statistics | 0.000111 |
| preparing | 0.000022 |
| executing | 0.000004 |
| Sorting result | 0.000002 |
| Sending data | 136.213836 |
| end | 0.000007 |
| query end | 0.000002 |
| freeing items | 0.004273 |
| storing result in query cache | 0.000010 |
| logging slow query | 0.000001 |
| logging slow query | 0.000002 |
| cleaning up | 0.000002 |
+--------------------------------+------------+
開発時の結果は次のとおりです。
+-------------+
| num_results |
+-------------+
| 3 |
+-------------+
1 row in set (0.08 sec)
このクエリのプロファイルは次のとおりです。
+--------------------------------+----------+
| Status | Duration |
+--------------------------------+----------+
| starting | 0.000022 |
| checking query cache for query | 0.000148 |
| Opening tables | 0.000025 |
| System lock | 0.000008 |
| Table lock | 0.000101 |
| optimizing | 0.000035 |
| statistics | 0.001019 |
| preparing | 0.000047 |
| executing | 0.000008 |
| Sorting result | 0.000005 |
| Sending data | 0.086565 |
| init | 0.000015 |
| optimizing | 0.000006 |
| executing | 0.000020 |
| end | 0.000004 |
| query end | 0.000004 |
| freeing items | 0.000028 |
| storing result in query cache | 0.000005 |
| removing tmp table | 0.000008 |
| closing tables | 0.000008 |
| logging slow query | 0.000002 |
| cleaning up | 0.000005 |
+--------------------------------+----------+
ユーザーやプロジェクトの内部結合を削除すると、クエリは 30 秒に短縮されます。
私が持っている最後の情報:
Mysqlserver と Apache は同じボックスにあり、実稼働用のボックスは 1 つだけです。
上から生産量:前と後。
top - 15:43:25 up 78 days, 12:11, 4 users, load average: 1.42, 0.99, 0.78
Tasks: 162 total, 2 running, 160 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.1%us, 50.4%sy, 0.0%ni, 49.5%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 4037868k total, 3772580k used, 265288k free, 243704k buffers
Swap: 3905528k total, 265384k used, 3640144k free, 1207944k cached
top - 15:44:31 up 78 days, 12:13, 4 users, load average: 1.94, 1.23, 0.87
Tasks: 160 total, 2 running, 157 sleeping, 0 stopped, 1 zombie
Cpu(s): 0.2%us, 50.6%sy, 0.0%ni, 49.3%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 4037868k total, 3834300k used, 203568k free, 243736k buffers
Swap: 3905528k total, 265384k used, 3640144k free, 1207804k cached
しかし、これは本番環境の通常の状態を適切に表したものではないため、クエリの実行以外で今日から取得したものをここに示します。
top - 11:04:58 up 79 days, 7:33, 4 users, load average: 0.39, 0.58, 0.76
Tasks: 156 total, 1 running, 155 sleeping, 0 stopped, 0 zombie
Cpu(s): 3.3%us, 2.8%sy, 0.0%ni, 93.9%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 4037868k total, 3676136k used, 361732k free, 271480k buffers
Swap: 3905528k total, 268736k used, 3636792k free, 1063432k cached
展開:これは途中でも後でも変わりません。
top - 15:47:07 up 110 days, 22:11, 7 users, load average: 0.17, 0.07, 0.06
Tasks: 210 total, 2 running, 208 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.1%us, 0.2%sy, 0.0%ni, 99.7%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 4111972k total, 1821100k used, 2290872k free, 238860k buffers
Swap: 4183036k total, 66472k used, 4116564k free, 921072k cached