我的备份脚本都是在凌晨执行的，经常在慢查询日志里面看到这样的信息：select * from table1;
之前一直很纳闷，最后才了解到原来是MYSQLDUMP搞的鬼。
因为MYSQLDUMP会为整个库来加一个全局锁定。
如果单纯用MYSQLDUMP进行全库备份会造成以下三个方面的影响。
1、服务器CPU严重阻塞。
2、磁盘I/O直线增加。
3、所有的查询都成了慢查询。
我现在的网站数据库大概是5个G左右，而且每天都有增大。
表结构是MYISAM,INNODB,MEMORY三者混合。
所以单纯用HOTCOPY工具恐怕有点困难。所以我今天简单变了一下我上次写的关于用OUTFILE来备份MYSQL的脚本。
可以解决上面说的三个缺点。
1、备份脚本内容
[david_yeung@localhost ~]$ cat fast_backup
#!/bin/sh
#
# Created by david yeung.
#
# 20080707.
#
# Backup mysql's full data.
#
DBNAME=$1
BACKUPDIR=/home/david_yeung/backup_new
USERNAME=backup_user
PASSWD=123456
TARNAME="$BACKUPDIR"/backup"$1"`date '+%Y%m%d'`
# Add your own database name here.
case "$1" in
my_site);;
*) exit;;
esac
# Get all the tables' name.
NUM=`/usr/local/mysql/bin/mysql -u$USERNAME -p$PASSWD -s -vv -e "show tables" -D $DBNAME|wc -l`
HEADNUM=`expr ${NUM} - 3`
TAILNUM=`expr ${NUM} - 7`
ARR1=`/usr/local/mysql/bin/mysql -u$USERNAME -p$PASSWD -s -vv -e "show tables" -D $DBNAME| head -n"$HEADNUM" | tail -n "$TAILNUM"`
ARR2=($ARR1)
i=0
while [ "$i" -lt "${#ARR2[@]}" ]
do
tmpFileName=${ARR2[$i]}
# The real dump process.
/usr/local/mysql/bin/mysqldump -u$USERNAME -p"$PASSWD" "$DBNAME" "$tmpFileName" >> "$TARNAME"
let "i++"
done
2、因为我们一直用存储过程，所以得单独备份出来。
[david_yeung@localhost ~]$ cat fast_sp
#!/bin/sh
# Created by david yeung 20080122.
#
# Backup site's routine.
TARNAME=/home/david_yeung/backup_new/spBackup"$1"`date '+%Y%m%d'`
/usr/local/mysql/bin/mysqldump -ubackup_user -p123456 -n -t -d -R my_site > "$TARNAME"
3、丢到计划任务里面去，就不管了。
[root@localhost backup_new]# crontab -l
0 01 * * * /home/david_yeung/fast_backup my_site
0 0 * * 5 /home/david_yeung/fast_sp
每天凌晨1点备份数据，每个周五凌晨备份存储过程。
4、因为有人说碰到要恢复单表的数据，所以把备份单表脚本也贴上。
#!/bin/sh
#
# Created by david yeung.
#
# 20080707.
#
# Backup mysql's full data.
#
DBNAME=$1
USERNAME=backup_user
PASSWD=123456
PREFIX=/home/david_yeung/backup_new/
DIRNAME=$PREFIX`date '+%Y%m%d'`
echo $TARNAME
# Add your own database name here.
case "$1" in
t_girl);;
*) exit;;
esac
if [ ! -d "$DIRNAME" ]
then
mkdir "$DIRNAME"
fi
# Get all the tables' name.
NUM=`/usr/local/mysql/bin/mysql -u$USERNAME -p$PASSWD -S/tmp/mysql50.sock -s -vv -e "show tables" -D $DBNAME|wc -l`
HEADNUM=`expr ${NUM} - 3`
TAILNUM=`expr ${NUM} - 7`
ARR1=`/usr/local/mysql/bin/mysql -u$USERNAME -p$PASSWD -S/tmp/mysql50.sock -s -vv -e "show tables" -D $DBNAME| head -n"$HEADNUM" | tail -n "$TAILNUM"`
ARR2=($ARR1)
i=0
while [ "$i" -lt "${#ARR2[@]}" ]
do
tmpFileName=${ARR2[$i]}
# The real dump process.
/usr/local/mysql/bin/mysqldump -u$USERNAME -p"$PASSWD" -S/tmp/mysql50.sock "$DBNAME" "$tmpFileName" > "$DIRNAME"/"$tmpFileName"
let "i++"
done
