环境： win 2003 , IIS6 + php 5 + MYSQL 5 服务器配置： inter S5000V 主板， 志强双核超线程CPU*2 ，内存 创见 667 2G*2 服务器 主要以 内容访问为主， 大概在10月底的时候突然在一次重启服务器后出现 经常 显示 connect fail的问题，后排查了很多原因，一直得不到解决，请高手指教。
事件提示当中 有提示 Changed limits: max_open_files: 2048 max_connections: 1910 table_cache: 64 网上查了 说是 调整 max_connections 或调整其他两个数值 ，这几个我全部都调整过了，还是不太合适 还有看到网上 说是一个 KB967723补丁 造成 频繁无法连接，但是我删除了 好像也是没有用
最近 几天这个提示越来越频繁了，刚刚重启就出现了，请高手帮忙啊
事件提示当中 有提示 Changed limits: max_open_files: 2048 max_connections: 1910 table_cache: 64 网上查了 说是 调整 max_connections 或调整其他两个数值 ，这几个我全部都调整过了，还是不太合适 还有看到网上 说是一个 KB967723补丁 造成 频繁无法连接，但是我删除了 好像也是没有用
最近 几天这个提示越来越频繁了，刚刚重启就出现了，请高手帮忙啊
另外显示一下mysql> show status like '%connection%';
+----------------------+-------+
| Variable_name | Value |
+----------------------+-------+
| Connections | 2 |
| Max_used_connections | 1 |
+----------------------+-------+
2 rows in set (0.00 sec)mysql>估计不是MYSQL的问题，是你WINDOWS操作系统的TCP/IP的联接限制。
如果你确认是这个问题，则到 windows 版去问一下吧。提供你的 winodws 的版本号，补丁号，以方便别人分析。
091211 15:54:43 InnoDB: Shutdown completed; log sequence number 0 84628116
091211 15:54:43 [Note] E:\MySQL5\bin\mysqld-nt: Shutdown complete091211 15:54:44 InnoDB: Started; log sequence number 0 84628116
091211 15:54:44 [Note] E:\MySQL5\bin\mysqld-nt: ready for connections.
Version: '5.0.41-community-nt' socket: '' port: 3306 MySQL Community Edition (GPL)
091211 16:01:18 [Note] E:\MySQL5\bin\mysqld-nt: Normal shutdown091211 16:01:18 [ERROR] E:\MySQL5\bin\mysqld-nt: Sort aborted
091211 16:01:18 [ERROR] E:\MySQL5\bin\mysqld-nt: Sort aborted
091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 214 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 212 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 210 user: 'webmaster' user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 206 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 203 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 199 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 197 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 191 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 187 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 186 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 184 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 183 user: 'webmaster'091211 16:01:20 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 181 user: 'webmaster'091211 16:29:40 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 99 user: 'webmaster'091211 16:29:40 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 96 user: 'webmaster'091211 16:29:40 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 95 user: 'webmaster'091211 16:29:40 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 94 user: 'webmaster'091211 16:29:40 [Warning] E:\MySQL5\bin\mysqld-nt: Forcing close of thread 93 user: 'webmaster'091211 16:29:40 InnoDB: Starting shutdown...
091211 16:29:43 InnoDB: Shutdown completed; log sequence number 0 84628116
091211 16:29:43 [Note] E:\MySQL5\bin\mysqld-nt: Shutdown complete091211 16:29:44 InnoDB: Started; log sequence number 0 84628116
091211 16:29:44 [Note] E:\MySQL5\bin\mysqld-nt: ready for connections.
Version: '5.0.41-community-nt' socket: '' port: 3306 MySQL Community Edition (GPL)
另外显示一下mysql> show status like '%connection%';
# ----------------------------------------------------------------------
# Generated by the MySQL Server Instance Configuration Wizard
#
#
# Installation Instructions
# ----------------------------------------------------------------------
#
# On Linux you can copy this file to /etc/my.cnf to set global options,
# mysql-data-dir/my.cnf to set server-specific options
# (@localstatedir@ for this installation) or to
# ~/.my.cnf to set user-specific options.
#
# On Windows you should keep this file in the installation directory
# of your server (e.g. C:\Program Files\MySQL\MySQL Server X.Y). To
# make sure the server reads the config file use the startup option
# "--defaults-file".
#
# To run run the server from the command line, execute this in a
# command line shell, e.g.
# mysqld --defaults-file="C:\Program Files\MySQL\MySQL Server X.Y\my.ini"
#
# To install the server as a Windows service manually, execute this in a
# command line shell, e.g.
# mysqld --install MySQLXY --defaults-file="C:\Program Files\MySQL\MySQL Server X.Y\my.ini"
#
# And then execute this in a command line shell to start the server, e.g.
# net start MySQLXY
#
#
# Guildlines for editing this file
# ----------------------------------------------------------------------
#
# In this file, you can use all long options that the program supports.
# If you want to know the options a program supports, start the program
# with the "--help" option.
#
# More detailed information about the individual options can also be
# found in the manual.
#
#
# CLIENT SECTION
# ----------------------------------------------------------------------
#
# The following options will be read by MySQL client applications.
# Note that only client applications shipped by MySQL are guaranteed
# to read this section. If you want your own MySQL client program to
# honor these values, you need to specify it as an option during the
# MySQL client library initialization.
#
[client]port=3306[mysql]default-character-set=gbk
# SERVER SECTION
# ----------------------------------------------------------------------
#
# The following options will be read by the MySQL Server. Make sure that
# you have installed the server correctly (see above) so it reads this
# file.
#
[mysqld]# The TCP/IP Port the MySQL Server will listen on
port=3306
#Path to installation directory. All paths are usually resolved relative to this.
basedir="E:/MySQL5/"#Path to the database root
datadir="E:/MySQL5/Data/"# The default character set that will be used when a new schema or table is
# created and no character set is defined
default-character-set=latin1# The default storage engine that will be used when create new tables when
default-storage-engine=INNODB# Set the SQL mode to strict
sql-mode="STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"# The maximum amount of concurrent sessions the MySQL server will
# allow. One of these connections will be reserved for a user with
# SUPER privileges to allow the administrator to login even if the
# connection limit has been reached.
max_connections=500# Query cache is used to cache SELECT results and later return them
# without actual executing the same query once again. Having the query
# cache enabled may result in significant speed improvements, if your
# have a lot of identical queries and rarely changing tables. See the
# "Qcache_lowmem_prunes" status variable to check if the current value
# is high enough for your load.
# Note: In case your tables change very often or if your queries are
# textually different every time, the query cache may result in a
# slowdown instead of a performance improvement.
query_cache_size=256M# The number of open tables for all threads. Increasing this value
# increases the number of file descriptors that mysqld requires.
# Therefore you have to make sure to set the amount of open files
# allowed to at least 4096 in the variable "open-files-limit" in
# section [mysqld_safe]
table_cache=512# Maximum size for internal (in-memory) temporary tables. If a table
# grows larger than this value, it is automatically converted to disk
# based table This limitation is for a single table. There can be many
# of them.
tmp_table_size=256M
# How many threads we should keep in a cache for reuse. When a client
# disconnects, the client's threads are put in the cache if there aren't
# more than thread_cache_size threads from before. This greatly reduces
# the amount of thread creations needed if you have a lot of new
# connections. (Normally this doesn't give a notable performance
# improvement if you have a good thread implementation.)
thread_cache_size=12#*** MyISAM Specific options# The maximum size of the temporary file MySQL is allowed to use while
# recreating the index (during REPAIR, ALTER TABLE or LOAD DATA INFILE.
# If the file-size would be bigger than this, the index will be created
# through the key cache (which is slower).
myisam_max_sort_file_size=100G# If the temporary file used for fast index creation would be bigger
# than using the key cache by the amount specified here, then prefer the
# key cache method. This is mainly used to force long character keys in
# large tables to use the slower key cache method to create the index.
myisam_max_extra_sort_file_size=100G# If the temporary file used for fast index creation would be bigger
# than using the key cache by the amount specified here, then prefer the
# key cache method. This is mainly used to force long character keys in
# large tables to use the slower key cache method to create the index.
myisam_sort_buffer_size=64M# Size of the Key Buffer, used to cache index blocks for MyISAM tables.
# Do not set it larger than 30% of your available memory, as some memory
# is also required by the OS to cache rows. Even if you're not using
# MyISAM tables, you should still set it to 8-64M as it will also be
# used for internal temporary disk tables.
key_buffer_size=200M# Size of the buffer used for doing full table scans of MyISAM tables.
# Allocated per thread, if a full scan is needed.
read_buffer_size=64K
read_rnd_buffer_size=16K# This buffer is allocated when MySQL needs to rebuild the index in
# REPAIR, OPTIMZE, ALTER table statements as well as in LOAD DATA INFILE
# into an empty table. It is allocated per thread so be careful with
# large settings.
sort_buffer_size=8M# Try number of CPU's*2 for thread_concurrency
thread_concurrency = 8#*** INNODB Specific options ***
innodb_data_home_dir="E:/Data/"# Use this option if you have a MySQL server with InnoDB support enabled
# but you do not plan to use it. This will save memory and disk space
# and speed up some things.
#skip-innodb# Additional memory pool that is used by InnoDB to store metadata
# information. If InnoDB requires more memory for this purpose it will
# start to allocate it from the OS. As this is fast enough on most
# recent operating systems, you normally do not need to change this
# value. SHOW INNODB STATUS will display the current amount used.
innodb_additional_mem_pool_size=2M# If set to 1, InnoDB will flush (fsync) the transaction logs to the
# disk at each commit, which offers full ACID behavior. If you are
# willing to compromise this safety, and you are running small
# transactions, you may set this to 0 or 2 to reduce disk I/O to the
# logs. Value 0 means that the log is only written to the log file and
# the log file flushed to disk approximately once per second. Value 2
# means the log is written to the log file at each commit, but the log
# file is only flushed to disk approximately once per second.
innodb_flush_log_at_trx_commit=1# The size of the buffer InnoDB uses for buffering log data. As soon as
# it is full, InnoDB will have to flush it to disk. As it is flushed
# once per second anyway, it does not make sense to have it very large
# (even with long transactions).
innodb_log_buffer_size=1M# InnoDB, unlike MyISAM, uses a buffer pool to cache both indexes and
# row data. The bigger you set this the less disk I/O is needed to
# access data in tables. On a dedicated database server you may set this
# parameter up to 80% of the machine physical memory size. Do not set it
# too large, though, because competition of the physical memory may
# cause paging in the operating system. Note that on 32bit systems you
# might be limited to 2-3.5G of user level memory per process, so do not
# set it too high.
innodb_buffer_pool_size=47M# Size of each log file in a log group. You should set the combined size
# of log files to about 25%-100% of your buffer pool size to avoid
# unneeded buffer pool flush activity on log file overwrite. However,
# note that a larger logfile size will increase the time needed for the
# recovery process.
innodb_log_file_size=24M# Number of threads allowed inside the InnoDB kernel. The optimal value
# depends highly on the application, hardware as well as the OS
# scheduler properties. A too high value may lead to thread thrashing.
innodb_thread_concurrency=18
用mysql命令工具连上去，然后执行 show status like '%connection%';
+----------------------+-------+
| Variable_name | Value |
+----------------------+-------+
| Connections | 102 |
| Max_used_connections | 53 |
+----------------------+-------+
2 rows in set (0.00 sec) mysql>
从这个看连接数远没有到达你的MYSQL的最大连接数 500.
091211 16:01:18 [Note] E:\MySQL5\bin\mysqld-nt: Normal shutdown
这儿是一个正确的关闭动作。MYSQL端看不出什么特别的了。 1。你的防火墙或者杀毒软件。
2。你的操作系统
+----------------------+-------+
| Variable_name | Value |
+----------------------+-------+
| Connections | 30709 |
| Max_used_connections | 31 |
+----------------------+-------+
2 rows in set (0.00 sec) 刚才有检查到 上面一个 Connections 达到一个很大的数值， 达到3万多了，这个是累积的连接数吗？
重启了一次MYSQL之后好像正常了，又少了
| Connections | 30709 | 是