我有使用ubuntu 14服务器的vps设置。我安装了灯堆。一切都很完美，但mysql服务器经常停止，我必须手动重启它。这是我的my.cnf mysql配置文件。
# The MySQL database server configuration file.
#
# You can copy this to one of:
# - "/etc/mysql/my.cnf" to set global options,
# - "~/.my.cnf" to set user-specific options.
#
# One can use all long options that the program supports.
# Run program with --help to get a list of available options and with
# --print-defaults to see which it would actually understand and use.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html
# This will be passed to all mysql clients
# It has been reported that passwords should be enclosed with ticks/quotes
# escpecially if they contain "#" chars...
# Remember to edit /etc/mysql/debian.cnf when changing the socket location.
[client]
port = 3306
socket = /var/run/mysqld/mysqld.sock
# Here is entries for some specific programs
# The following values assume you have at least 32M ram
# This was formally known as [safe_mysqld]. Both versions are currently parsed.
[mysqld_safe]
socket = /var/run/mysqld/mysqld.sock
nice = 0
[mysqld]
#
# * Basic Settings
#
user = mysql
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
port = 3306
basedir = /usr
datadir = /var/lib/mysql
tmpdir = /tmp
lc-messages-dir = /usr/share/mysql
skip-external-locking
#
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
bind-address = 127.0.0.1
#
# * Fine Tuning
#
key_buffer = 16M
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 = 16M
#
# * Logging and Replication
#
# Both location gets rotated by the cronjob.
# Be aware that this log type is a performance killer.
# As of 5.1 you can enable the log at runtime!
#general_log_file = /var/log/mysql/mysql.log
#general_log = 1
#
# Error log - should be very few entries.
#
log_error = /var/log/mysql/error.log
#
# Here you can see queries with especially long duration
#log_slow_queries = /var/log/mysql/mysql-slow.log
#long_query_time = 2
#log-queries-not-using-indexes
#
# The following can be used as easy to replay backup logs or for replication.
# note: if you are setting up a replication slave, see README.Debian about
# other settings you may need to change.
#server-id = 1
#log_bin = /var/log/mysql/mysql-bin.log
expire_logs_days = 10
max_binlog_size = 100M
#binlog_do_db = include_database_name
#binlog_ignore_db = include_database_name
#
# * InnoDB
#
# InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/.
# Read the manual for more InnoDB related options. There are many!
#
# * Security Features
#
# Read the manual, too, if you want chroot!
# chroot = /var/lib/mysql/
#
# For generating SSL certificates I recommend the OpenSSL GUI "tinyca".
#
# ssl-ca=/etc/mysql/cacert.pem
# ssl-cert=/etc/mysql/server-cert.pem
# ssl-key=/etc/mysql/server-key.pem
[mysqldump]
quick
quote-names
max_allowed_packet = 16M
[mysql]
#no-auto-rehash # faster start of mysql but no tab completition
[isamchk]
key_buffer = 16M
#
# * IMPORTANT: Additional settings that can override those from this file!
# The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/
以下是我的mysqltuner输出。
-------- General Statistics ------------------------------------------------
[--] Skipped version check for MySQLTuner script
[OK] Currently running supported MySQL version 5.5.49-0ubuntu0.14.04.1
[OK] Operating on 64-bit architecture
-------- Storage Engine Statistics -------------------------------------------
[--] Status: +Archive -BDB -Federated +InnoDB -ISAM -NDBCluster
[--] Data in MyISAM tables: 38K (Tables: 34)
[--] Data in PERFORMANCE_SCHEMA tables: 0B (Tables: 17)
[--] Data in InnoDB tables: 11M (Tables: 101)
[!!] Total fragmented tables: 101
-------- Security Recommendations -------------------------------------------
[OK] All database users have passwords assigned
-------- Performance Metrics -------------------------------------------------
[--] Up for: 1h 13m 27s (2K q [0.464 qps], 130 conn, TX: 5M, RX: 332K)
[--] Reads / Writes: 81% / 19%
[--] Total buffers: 192.0M global + 2.7M per thread (151 max threads)
[!!] Maximum possible memory usage: 597.8M (121% of installed RAM)
[OK] Slow queries: 0% (0/2K)
[OK] Highest usage of available connections: 7% (12/151)
[OK] Key buffer size / total MyISAM indexes: 16.0M/196.0K
[OK] Query cache efficiency: 33.9% (493 cached / 1K selects)
[OK] Query cache prunes per day: 0
[OK] Sorts requiring temporary tables: 0% (0 temp sorts / 77 sorts)
[!!] Temporary tables created on disk: 33% (166 on disk / 498 total)
[OK] Thread cache hit rate: 90% (12 created / 130 connections)
[OK] Table cache hit rate: 94% (178 open / 189 opened)
[OK] Open file limit used: 11% (116/1K)
[OK] Table locks acquired immediately: 100% (1K immediate / 1K locks)
[OK] InnoDB data size / buffer pool: 11.9M/128.0M
-------- Recommendations -----------------------------------------------------
General recommendations:
Run OPTIMIZE TABLE to defragment tables for better performance
MySQL started within last 24 hours - recommendations may be inaccurate
Reduce your overall MySQL memory footprint for system stability
Enable the slow query log to troubleshoot bad queries
When making adjustments, make tmp_table_size/max_heap_table_size equal
Reduce your SELECT DISTINCT queries without LIMIT clauses
Variables to adjust:
*** MySQL's maximum memory usage is dangerously high ***
*** Add RAM before increasing MySQL buffer variables ***
tmp_table_size (> 16M)
max_heap_table_size (> 16M)
这是我的记忆使用
Every 5.0s: free -m Sun Jul 3 03:12:12 2016
total used free shared buffers cached
记忆：490 476 13 64 10 183 - / + buffers / cache：281 208 交换：0 0 0
这里有什么不妥。我的my.cnf上有一些错误配置或其他东西正在杀死mysql。请帮我找到问题。
答案 0 :(得分：2)
mysql可能内存不足。它发生在您的系统缺少交换时（即当内存耗尽时，程序无法从主内存传输到“交换”文件以防止系统内存故障）。
从Linux.com转换说明：
Linux将其物理RAM（随机存取存储器）划分为chucks 内存称为页面。交换是一页内存的过程 被复制到硬盘上的预配置空间，称为swap 空间，释放那页内存。合并后的尺寸 物理内存和交换空间是虚拟内存的数量 可用。
您可以调整“innodb_buffer_pool_size”以减少内存中的索引和缓存占用空间。
理想情况下，您将缓冲池的大小设置为与值一样大的值 实用，为服务器上的其他进程留下足够的内存 没有过多的分页运行。缓冲池越大，越多 InnoDB就像一个内存数据库，一次从磁盘读取数据 然后在后续读取期间从内存中访问数据。 使用innodb_buffer_pool_size配置缓冲池大小 配置选项。
解决方案：
innodb_buffer_pool_size=64M 然后制作一个交换文件：
并将其添加到/etc/fstab：
/swapfile none swap sw 0 0