[Extmail] 请问那些自动生成的计划任务分别是什么意思？

请问那些自动生成的计划任务分别是什么意思？0 4 * * * /var/www/extsuite/extman/tools/expireusers.pl -all postmaster@c
30 4 * * * /var/www/extsuite/extman/tools/reportusage.pl -all /home/domai
0 0 1 * * wget -N -P /usr/share/spamassassin www.ccert.edu.cn/spam/sa/Chi
0 5 * * sun /usr/local/slockd/tools/log-rotate /usr/bin/gzip
0 0 * * * /usr/bin/mysql -u dspam -p'123456' dspam < /usr/share/dspam/sql
0 0 * * * /usr/bin/dspam_logrotate -a 30 -d /var/spool/dspam/data
* * * * * /usr/bin/php /var/www/extsuite/monitor/update.php &> /dev/null

01 */1 * * * /usr/bin/perl /var/www/extsuite/extmail/tools/cleansid.pl /v

4点发送用户状态报告（每天postmaster会收到二封邮件，就是这个自动发送的）
0 4 * * * /var/www/extsuite/extman/tools/expireusers.pl -all postmaster@c
30 4 * * * /var/www/extsuite/extman/tools/reportusage.pl -all /home/domai
每周一升级垃圾关键字
0 0 1 * * wget -N -P /usr/share/spamassassin www.ccert.edu.cn/spam/sa/Chi
每天5点打包log-rotate日志
0 5 * * sun /usr/local/slockd/tools/log-rotate /usr/bin/gzip
每天0点学习的数据导入到mysql （判断垃圾邮件，给邮件评分）
0 0 * * * /usr/bin/mysql -u dspam -p'123456' dspam < /usr/share/dspam/sql
0 0 * * * /usr/bin/dspam_logrotate -a 30 -d /var/spool/dspam/data
运行update.php升级 update.php里写的是什么程序就是干什么
* * * * * /usr/bin/php /var/www/extsuite/monitor/update.php &> /dev/null
01 */1 * * * /usr/bin/perl /var/www/extsuite/extmail/tools/cleansid.pl /v