【发布时间】：2023-02-26 05:35:45
【问题描述】：
您好，作为 Microsoft SQL 的 SQL 开发人员，我有相当多的经验，但作为 DBA 几乎没有经验，我才刚刚开始学习 MySQL。基本上，我有一个预定的存储过程，它可以正常运行几个小时，然后突然停止执行，运行速度慢了将近 30 倍。 （不是锁定/阻塞问题）
我在一台几乎没有任何活动的新服务器上生成大量随机测试数据，我设置为每 10 分钟运行一次 EVENT。我设置的事件执行一些非常基本的日志记录并执行两个存储过程，一个填充临时表，另一个填充最终表（这更类似于数据在生产中进入系统的方式）。
事件
- 每 10 分钟执行一次 2 个存储过程
- 将运行时间记录到表格中
- 读取日志表，如果上次执行未完成则不执行
delimiter $$
CREATE EVENT Score_Stage_Processing_ANDTEST
ON SCHEDULE EVERY 10 minute
STARTS CURRENT_TIMESTAMP
ON COMPLETION NOT PRESERVE
ENABLE
DO
BEGIN
set @ProcName = 'Score_Stage_Processing_ANDTEST';
set @EndDate = (
select EndDate
from Event_Log el
where Name = @ProcName
order by StartDate desc
limit 1);
set @StartDate = (
select StartDate
from Event_Log el
where Name = @ProcName
order by StartDate desc
limit 1);
-- Only execute if last execution was successful.
IF ((@StartDate is not null and @EndDate is not null) or (@StartDate is null and @EndDate is null))
THEN
INSERT INTO Event_Log(Name, StartDate, EndDate)
VALUES(@ProcName, now(), null);
Set @ID = Last_Insert_ID();
set bulk_insert_buffer_size = 1024*1024*256; -- default 1024*1024*8
call test_create_scores(1000);
call Score_Stage_Processing();
update Event_Log
set EndDate = now()
where ID = @ID;
END IF;
end $$
delimiter ;
存储过程 1
- 生成 70k 随机记录并将它们放入临时表中进行处理
CREATE DEFINER=`root`@`localhost` PROCEDURE `test_create_scores`(
IN in_NumInsertS int
)
sp: BEGIN
DECLARE i INT DEFAULT 1;
set @max = in_NumInsertS;
while i <= @max
DO
Set @STD = 5000;
Set @Mean = 20000;
-- 20 random levels Unbreaking New
insert into stg_Score_Pending (LevelID, SteamID, Score, Stress, isUnbreaking)
select LevelID
, FLOOR(RAND() * (1000000000-100000000) + 100000000) as SteamID -- pretty much always new people
, floor(((RAND() * 2 - 1) + (RAND() * 2 - 1) + (RAND() * 2 - 1)) * @STD + @Mean) as RandScore
, FLOOR(RAND() * (9900-6000) + 6000) as Stress -- between 60 and 99
, 1 as isUnbreaking
from Level
where LevelType = 'Campaign'
order by rand()
limit 40;
-- 15 random levels breaking new players
insert into stg_Score_Pending (LevelID, SteamID, Score, Stress, isUnbreaking)
select LevelID
, FLOOR(RAND() * (1000000000-100000000) + 100000000) as SteamID -- pretty much always new people
, floor(((RAND() * 2 - 1) + (RAND() * 2 - 1) + (RAND() * 2 - 1)) * @STD + @Mean) as RandScore
, 10000 as Stress -- between 60 and 99
, 0 as isUnbreaking
from Level
where LevelType = 'Campaign'
order by rand()
limit 30;
SET i = i + 1;
end while;
leave sp;
END;
存储过程 2
- 根据需要从暂存中删除重复记录
- 插入或更新记录两个 2 个不同的表（~70k 到两个不同的表）
CREATE DEFINER=`root`@`localhost` PROCEDURE `score_stage_processing`()
BEGIN
set @BatchSize = 10000;
set @BatchCount = 200;
set @InitialMax = (select max(ID) from `stg_Score_Pending`);
set @m = 2147483647;
-- batches and caps number of updates
set @MinID = (select min(ID) from `stg_Score_Pending`);
set @MaxID = @minID + @BatchSize;
while @BatchCount > 0 and @InitialMax > @MaxID - @BatchSize
do
-- Identify Pending Miniumum Stress and Score
create temporary table if not exists tmp_ScoreBudgetStress
(primary key tmp_stress_pkey (LevelID, SteamID))
select ssp.LevelID
, ssp.SteamID
, case when min(ssp.Score) < ifnull(min(sb.Score),@m) Then min(ssp.Score) else min(sb.Score) end as MinScore
, case when min(ssp.Stress) < ifnull(min(ss.Score),@m) then min(ssp.Stress) else min(ss.Score) end as MinStress
from stg_Score_Pending ssp
left join Score_Budget sb on sb.LevelID = ssp.LevelID -- This prevents INCREASING the score
and sb.SteamID = ssp.SteamID
and sb.Score < ssp.Score
left join Score_Stress ss on ss.LevelID = ssp.LevelID -- This prevents INCREASING the score
and ss.SteamID = ssp.SteamID
and ss.Score < sb.Score
where ssp.id <= @MaxID
group by ssp.LevelID, ssp.SteamID;
-- Identify Pending Minimum Unbreaking
create temporary table if not exists tmp_ScoreUnbreakingBudget
(primary key tmp_budget_pkey (LevelID, SteamID))
select ssp.LevelID
, ssp.SteamID
, case when min(ssp.Score) < ifnull(min(sb.Score),@m) Then min(ssp.Score) else min(sb.Score) end as MinUnbreakingScore
from stg_Score_Pending ssp
left join Score_Budget sb on sb.LevelID = ssp.LevelID -- This prevents INCREASING the score
and sb.SteamID = ssp.SteamID
and sb.Score < ssp.Score
where ssp.id <= @MaxID
and ssp.isUnbreaking = 1
group by ssp.LevelID, SteamID;
-- Updates to SCORE BUDGET
update Score_Budget sb
inner join tmp_ScoreBudgetStress s on s.LevelID = sb.LevelID -- inner join serves as existance check (update all scores that exists in table already)
and s.SteamID = sb.SteamID
left join tmp_ScoreUnbreakingBudget u on u.LevelID = sb.LevelID
and u.SteamID = sb.SteamID
set sb.Score = s.MinScore
, sb.ScoreUnbreaking = u.MinUnbreakingScore
, sb.hasNoUnbreaking = case when u.MinUnbreakingScore is null then 1 else 0 end;
insert into Score_Budget (LevelID, SteamID, Score, ScoreUnbreaking, hasNoUnbreaking, SampleKey)
select s.LevelID
, s.SteamID
, s.MinScore
, u.MinUnbreakingScore
, case when u.MinUnbreakingScore is null then 1 else 0 end
, case floor(rand() * 10)
when 0 then 1 -- 10%
when 1 then 2 -- 30%
when 2 then 2
when 3 then 2
when 4 then 3 -- 60%
when 5 then 3
when 6 then 3
when 7 then 3
when 8 then 3
when 9 then 3
end as SampleKey
from tmp_ScoreBudgetStress s
left join tmp_ScoreUnbreakingBudget u on u.LevelID = s.LevelID
and u.SteamID = s.SteamID
where not exists (
select 1
from Score_Budget sb
where sb.LevelID = s.LevelID
and sb.SteamID = s.SteamID
);
-- Updates to SCORE STRESS
update Score_Stress ss
inner join tmp_ScoreBudgetStress s on s.LevelID = ss.LevelID -- inner join serves as existance check (update all scores that exists in table already)
and s.SteamID = ss.SteamID
left join tmp_ScoreUnbreakingBudget u on u.LevelID = ss.LevelID
and u.SteamID = ss.SteamID
set ss.Score = s.MinStress;
insert into Score_Stress (LevelID, SteamID, Score, SampleKey)
select s.LevelID
, s.SteamID
, s.MinStress
, case floor(rand() * 10)
when 0 then 1 -- 10%
when 1 then 2 -- 30%
when 2 then 2
when 3 then 2
when 4 then 3 -- 60%
when 5 then 3
when 6 then 3
when 7 then 3
when 8 then 3
when 9 then 3
end as SampleKey
from tmp_ScoreBudgetStress s
left join tmp_ScoreUnbreakingBudget u on u.LevelID = s.LevelID
and u.SteamID = s.SteamID
where not exists (
select 1
from Score_Stress ss
where ss.LevelID = s.LevelID
and ss.SteamID = s.SteamID
);
-- Clear Out Staging Table
Delete d From stg_Score_Pending d Where id <= @MaxID;
-- Drop temporary tables
drop temporary table if exists tmp_ScoreBudgetStress;
drop temporary table if exists tmp_ScoreUnbreakingBudget;
set @MaxID = @MaxID + @BatchSize;
set @BatchCount = @BatchCount - 1;
end while;
END;
主要问题日志表显示事件开始和结束很快，然后突然开始花费大量时间。例如，我最后一次尝试事件在大约 30 秒内成功运行。然后事件突然开始每次执行需要 15 分钟。 （我有特殊处理以确保它在运行时不会启动） SS of Custom Event Log Showing fast execution then slow
事件开始缓慢运行后，我必须停止事件几个小时不运行作业，然后稍后再试。除了等待并重试（通常是第二天）之外，我不知道我需要做什么来立即修复它
我猜我觉得服务器正在做两件事之一
- 服务器获得错误的执行计划。添加越来越多的行后，表统计信息变得过时，MySQL 无法找到好的计划。我尝试将
analyze table添加到事件中，但这似乎并没有重置问题或阻止它发生。 - 一些内存缓冲区已满，我需要等待它被刷新。我试过将变量
bulk_insert_buffer_size从 8MB 增加到 256MB 但没有效果。我还向事件添加了 set 命令以尝试确保它保持更新。笔记：没有锁定表，这是服务器上运行的唯一进程，除了我之外没有人连接到它。当我检查
show full processlist时它运行缓慢，没有其他进程在运行我怀疑我需要更改某些服务器配置或需要清除某种缓存以防止突然变慢。
到目前为止，我主要只是尝试编辑几个不同的变量。我还尝试过重新启动服务器，刷新我知道的缓冲区，分析变化很大的表。
set bulk_insert_buffer_size = 1024*1024*256; -- 256mb default 1024*1024*8 set persist key_buffer_size = 1024*1024*1024; -- 1gb default 1024*1024*16 (recommends 25 to 30 percent of total memory on server) set innodb_buffer_pool_size = 1024*1024*1024*13; -- 13gb default 1024*1024*128感谢您的帮助和时间！
编辑：DDL
CREATE TABLE `stg_Score_Pending` ( `ID` bigint NOT NULL AUTO_INCREMENT, `LevelID` varchar(20) NOT NULL, `SteamID` bigint NOT NULL, `Score` int NOT NULL, `isUnbreaking` bit(1) NOT NULL, `Stress` int NOT NULL, PRIMARY KEY (`ID`), KEY `ix_stg_Score_Pending_LevelID_SteamID` (`LevelID`,`SteamID`) ) ENGINE=InnoDB AUTO_INCREMENT=16948201 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci ROW_FORMAT=COMPRESSED; CREATE TABLE `Score_Budget` ( `ID` int NOT NULL AUTO_INCREMENT, `LevelID` varchar(20) NOT NULL, `SteamID` bigint NOT NULL, `Score` int NOT NULL, `ScoreUnbreaking` int DEFAULT NULL, `hasNoUnbreaking` bit(1) NOT NULL, `SampleKey` tinyint NOT NULL, PRIMARY KEY (`ID`), UNIQUE KEY `ux_Score_Budget_LevelID_SteamID` (`LevelID`,`SteamID`), KEY `ix_Score_Budget_LevelID_unbreaking` (`LevelID`,`SampleKey`,`hasNoUnbreaking`,`ScoreUnbreaking`), KEY `ix_Score_Budget_LevelID_overall` (`LevelID`,`Score`) ) ENGINE=InnoDB AUTO_INCREMENT=14067791 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci ROW_FORMAT=COMPRESSED; CREATE TABLE `Score_Stress` ( `ID` int NOT NULL AUTO_INCREMENT, `LevelID` varchar(20) NOT NULL, `SteamID` bigint NOT NULL, `Score` int NOT NULL, `SampleKey` tinyint NOT NULL, PRIMARY KEY (`ID`), UNIQUE KEY `ux_Score_Stress_LevelID_SteamID` (`LevelID`,`SteamID`), KEY `ix_Score_Stress_LevelID_overall` (`LevelID`,`SampleKey`,`Score`) ) ENGINE=InnoDB AUTO_INCREMENT=14067791 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci ROW_FORMAT=COMPRESSED;
【问题讨论】：
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当服务器慢得可怜时请求额外的数据库信息，拜托。 RAM 大小、核心数、MySQL 主机服务器上的任何 SSD 或 NVME 设备？在 justpaste.it 上发布文本数据并共享链接。从您的 SSH 登录根目录，文本结果：A) SELECT COUNT(*), sum(data_length), sum(index_length), sum(data_free) FROM information_schema.tables; B) 显示全局状态；至少 24 小时正常运行后 C) 显示全局变量； D) 显示完整的流程列表； E) 状态；不显示状态，只是状态； G) 显示引擎创新状态；为服务器工作负载调优分析提供建议。
-
在 justpaste.it 上发布文本数据并共享链接。其他非常有用的操作系统信息包括 - 请 htop 第一页，如果可用，TERMINATE，top -b -n 1 用于最活跃的应用程序，top -b -n 1 -H 用于 mysql 线程内存和 cpu 使用的详细信息，ulimit - a 用于限制列表，iostat -xm 5 3 用于设备和核心/cpu 计数的 IOPS，df -h 用于已用 - 设备可用空间，df -i 用于设备 inode 信息，free -h 用于已用 - 空闲内存：和 Swap:、cat /proc/meminfo 包括 VMallocUused，为服务器工作负载调优分析提供建议。
标签： mysql database-performance database-administration