mysql - 什么Mysql使用大量CPU
问题描述
一年前我买了一个 DigitalOcean 液滴。这个月我收到了很高的流量（如我所料），但我的页面真的很慢，偶尔会出现 5xx http 错误。
我使用 Laravel Lumen 作为 API，使用 Nextjs 作为前端。我没有接触 mysql 配置，因为我什么都不知道，我只是让它来了。我对mysql配置一无所知。
我认为这是 Mysql 的问题，因为我运行了 htop 命令并看到了它的多个进程，并且 CPU 消耗很高。
我的服务器具有以下规格：
- 2GB 内存
- 2个vCPU
- Ubuntu 10.04（LAMP一键镜像）
MysqlTuner 报告：
[--] Skipped version check for MySQLTuner script
[OK] Logged in using credentials from Debian maintenance account.
[OK] Currently running supported MySQL version 5.7.31-0ubuntu0.18.04.1
[OK] Operating on 64-bit architecture
-------- Log file Recommendations ------------------------------------------------------------------
[OK] Log file /var/log/mysql/error.log exists
[--] Log file: /var/log/mysql/error.log(0B)
[OK] Log file /var/log/mysql/error.log is readable.
[!!] Log file /var/log/mysql/error.log is empty
[OK] Log file /var/log/mysql/error.log is smaller than 32 Mb
[OK] /var/log/mysql/error.log doesn't contain any warning.
[OK] /var/log/mysql/error.log doesn't contain any error.
[--] 0 start(s) detected in /var/log/mysql/error.log
[--] 0 shutdown(s) detected in /var/log/mysql/error.log
-------- Storage Engine Statistics -----------------------------------------------------------------
[--] Status: +ARCHIVE +BLACKHOLE +CSV -FEDERATED +InnoDB +MEMORY +MRG_MYISAM +MyISAM +PERFORMANCE_SCHEMA
[--] Data in InnoDB tables: 12.2M (Tables: 33)
[OK] Total fragmented tables: 0
-------- Analysis Performance Metrics --------------------------------------------------------------
[--] innodb_stats_on_metadata: OFF
[OK] No stat updates during querying INFORMATION_SCHEMA.
-------- Security Recommendations ------------------------------------------------------------------
[OK] There are no anonymous accounts for any database users
[OK] All database users have passwords assigned
[!!] There is no basic password file list!
-------- CVE Security Recommendations --------------------------------------------------------------
[--] Skipped due to --cvefile option undefined
-------- Performance Metrics -----------------------------------------------------------------------
[--] Up for: 9h 28m 38s (8M q [238.113 qps], 215K conn, TX: 2G, RX: 987M)
[--] Reads / Writes: 99% / 1%
[--] Binary logging is disabled
[--] Physical Memory : 1.9G
[--] Max MySQL memory : 2.7G
[--] Other process memory: 0B
[--] Total buffers: 176.0M global + 17.1M per thread (151 max threads)
[--] P_S Max memory usage: 72B
[--] Galera GCache Max memory usage: 0B
[OK] Maximum reached memory usage: 295.4M (14.82% of installed RAM)
[!!] Maximum possible memory usage: 2.7G (138.10% of installed RAM)
[!!] Overall possible memory usage with other process exceeded memory
[OK] Slow queries: 0% (0/8M)
[OK] Highest usage of available connections: 4% (7/151)
[OK] Aborted connections: 0.00% (0/215114)
[!!] name resolution is active : a reverse name resolution is made for each new connection and can reduce performance
[OK] Query cache is disabled by default due to mutex contention on multiprocessor machines.
[OK] Sorts requiring temporary tables: 0% (1 temp sorts / 77K sorts)
[OK] No joins without indexes
[OK] Temporary tables created on disk: 0% (0 on disk / 1M total)
[OK] Thread cache hit rate: 99% (8 created / 215K connections)
[OK] Table cache hit rate: 96% (224 open / 231 opened)
[OK] table_definition_cache(1400) is upper than number of tables(312)
[OK] Open file limit used: 0% (14/5K)
[OK] Table locks acquired immediately: 100% (102 immediate / 102 locks)
-------- Performance schema ------------------------------------------------------------------------
[--] Memory used by P_S: 72B
[--] Sys schema is installed.
-------- ThreadPool Metrics ------------------------------------------------------------------------
[--] ThreadPool stat is disabled.
-------- MyISAM Metrics ----------------------------------------------------------------------------
[!!] Key buffer used: 18.3% (3M used / 16M cache)
[OK] Key buffer size / total MyISAM indexes: 16.0M/43.0K
[!!] Read Key buffer hit rate: 50.0% (6 cached / 3 reads)
-------- InnoDB Metrics ----------------------------------------------------------------------------
[--] InnoDB is enabled.
[--] InnoDB Thread Concurrency: 0
[OK] InnoDB File per table is activated
[OK] InnoDB buffer pool / data size: 128.0M/12.2M
[OK] Ratio InnoDB log file size / InnoDB Buffer pool size: 16.0M * 2/128.0M should be equal to 25%
[OK] InnoDB buffer pool instances: 1
[--] Number of InnoDB Buffer Pool Chunk : 1 for 1 Buffer Pool Instance(s)
[OK] Innodb_buffer_pool_size aligned with Innodb_buffer_pool_chunk_size & Innodb_buffer_pool_instances
[OK] InnoDB Read buffer efficiency: 100.00% (12270183505 hits/ 12270184226 total)
[!!] InnoDB Write Log efficiency: 239.53% (103 hits/ 43 total)
[OK] InnoDB log waits: 0.00% (0 waits / 146 writes)
-------- AriaDB Metrics ----------------------------------------------------------------------------
[--] AriaDB is disabled.
-------- TokuDB Metrics ----------------------------------------------------------------------------
[--] TokuDB is disabled.
-------- XtraDB Metrics ----------------------------------------------------------------------------
[--] XtraDB is disabled.
-------- Galera Metrics ----------------------------------------------------------------------------
[--] Galera is disabled.
-------- Replication Metrics -----------------------------------------------------------------------
[--] Galera Synchronous replication: NO
[--] No replication slave(s) for this server.
[--] Binlog format: ROW
[--] XA support enabled: ON
[--] Semi synchronous replication Master: Not Activated
[--] Semi synchronous replication Slave: Not Activated
[--] This is a standalone server
-------- Recommendations ---------------------------------------------------------------------------
General recommendations:
MySQL was started within the last 24 hours - recommendations may be inaccurate
Reduce your overall MySQL memory footprint for system stability
Dedicate this server to your database for highest performance.
Configure your accounts with ip or subnets only, then update your configuration with skip-name-resolve=1
顶部
