查看系统的进程
[weiyuan@weiyuan ~]$ ps aux
[weiyuan@weiyuan ~]$ ps aux USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 1 0.0 0.0 3792 1436 ? Ss 02:35 0:01 /sbin/init root 2 0.0 0.0 0 0 ? S 02:35 0:00 [kthreadd] root 3 0.0 0.0 0 0 ? S 02:35 0:00 [migration/0] root 4 0.0 0.0 0 0 ? S 02:35 0:00 [ksoftirqd/0] root 5 0.0 0.0 0 0 ? S 02:35 0:00 [migration/0] root 6 0.0 0.0 0 0 ? S 02:35 0:00 [watchdog/0] root 7 0.0 0.0 0 0 ? S 02:35 0:00 [events/0] root 8 0.0 0.0 0 0 ? S 02:35 0:00 [cgroup] root 9 0.0 0.0 0 0 ? S 02:35 0:00 [khelper] root 10 0.0 0.0 0 0 ? S 02:35 0:00 [netns] root 11 0.0 0.0 0 0 ? S 02:35 0:00 [async/mgr] root 12 0.0 0.0 0 0 ? S 02:35 0:00 [pm] root 13 0.0 0.0 0 0 ? S 02:35 0:00 [sync_supers] root 14 0.0 0.0 0 0 ? S 02:35 0:00 [bdi-default] root 15 0.0 0.0 0 0 ? S 02:35 0:00 [kintegrityd/0] root 16 0.0 0.0 0 0 ? S 02:35 0:00 [kblockd/0] root 17 0.0 0.0 0 0 ? S 02:35 0:00 [kacpid] root 18 0.0 0.0 0 0 ? S 02:35 0:00 [kacpi_notify] root 19 0.0 0.0 0 0 ? S 02:35 0:00 [kacpi_hotplug] root 20 0.0 0.0 0 0 ? S 02:35 0:00 [ata_aux] root 21 0.0 0.0 0 0 ? S 02:35 0:00 [ata_sff/0] root 22 0.0 0.0 0 0 ? S 02:35 0:00 [ksuspend_usbd] root 23 0.0 0.0 0 0 ? S 02:35 0:00 [khubd] root 24 0.0 0.0 0 0 ? S 02:35 0:00 [kseriod] root 25 0.0 0.0 0 0 ? S 02:35 0:00 [md/0] root 26 0.0 0.0 0 0 ? S 02:35 0:00 [md_misc/0] root 27 0.0 0.0 0 0 ? S 02:35 0:00 [linkwatch] root 28 0.0 0.0 0 0 ? S 02:35 0:00 [khungtaskd] root 29 0.0 0.0 0 0 ? S 02:35 0:00 [kswapd0] root 30 0.0 0.0 0 0 ? SN 02:35 0:00 [ksmd] root 31 0.0 0.0 0 0 ? S 02:35 0:00 [aio/0] root 32 0.0 0.0 0 0 ? S 02:35 0:00 [crypto/0] root 37 0.0 0.0 0 0 ? S 02:35 0:00 [kthrotld/0] root 38 0.0 0.0 0 0 ? S 02:35 0:00 [pciehpd] root 40 0.0 0.0 0 0 ? S 02:35 0:00 [kpsmoused] root 41 0.0 0.0 0 0 ? S 02:35 0:00 [usbhid_resumer] root 72 0.0 0.0 0 0 ? S 02:35 0:00 [kstriped] root 142 0.0 0.0 0 0 ? S 02:35 0:00 [scsi_eh_0] root 143 0.0 0.0 0 0 ? S 02:35 0:00 [scsi_eh_1] root 152 0.0 0.0 0 0 ? S 02:35 0:00 [mpt_poll_0] root 153 0.0 0.0 0 0 ? S 02:35 0:00 [mpt/0] root 154 0.0 0.0 0 0 ? S 02:35 0:00 [scsi_eh_2] root 293 0.0 0.0 0 0 ? S 02:35 0:00 [kdmflush] root 295 0.0 0.0 0 0 ? S 02:35 0:00 [kdmflush] root 312 0.0 0.0 0 0 ? S 02:35 0:00 [jbd2/dm-0-8] root 313 0.0 0.0 0 0 ? S 02:35 0:00 [ext4-dio-unwrit] root 403 0.0 0.0 2912 1212 ? S<s 02:35 0:00 /sbin/udevd -d root 664 0.0 0.0 0 0 ? S 02:35 0:00 [flush-253:0] root 822 0.0 0.0 0 0 ? S 02:35 0:00 [vmmemctl] root 926 0.0 0.0 0 0 ? S 02:35 0:00 [jbd2/sda1-8] root 927 0.0 0.0 0 0 ? S 02:35 0:00 [ext4-dio-unwrit] root 1024 0.0 0.0 0 0 ? S 02:35 0:00 [kauditd] root 1187 0.0 0.0 12932 812 ? S<sl 02:35 0:00 auditd root 1212 0.0 0.0 36164 1580 ? Sl 02:35 0:00 /sbin/rsyslogd -i /var/run/syslogd.pid -c 5 rpc 1254 0.0 0.0 2576 796 ? Ss 02:35 0:00 rpcbind root 1361 0.0 0.5 16060 13068 ? Ss 02:35 0:00 /usr/bin/perl /home/weiyuan/work/webmin-1.801/miniserv.pl /etc/webmin/miniserv.conf dbus 1376 0.0 0.0 13736 1456 ? Ssl 02:35 0:00 dbus-daemon --system
top - 06:15:08 up 3:39, 1 user, load average: 0.00, 0.00, 0.00
Tasks: 121 total, 1 running, 120 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.3%us, 0.3%sy, 0.0%ni, 99.3%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 2247040k total, 403276k used, 1843764k free, 61348k buffers
Swap: 2392056k total, 0k used, 2392056k free, 197896k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1796 root 20 0 67800 20m 5680 S 0.0 0.9 0:01.68 Xorg
1931 gdm 20 0 84884 15m 12m S 0.0 0.7 0:00.50 gdm-simple-gree
1361 root 20 0 16060 12m 1580 S 0.0 0.6 0:00.37 miniserv.pl
1915 gdm 20 0 63632 11m 9532 S 0.0 0.5 0:00.99 gnome-settings-
[root@weiyuan weiyuan]# ps aux | grep httpd
root 3078 0.0 0.0 4968 2168 ? Ss 03:50 0:00 /usr/local/apache2/bin/httpd -k start
daemon 3079 0.0 0.0 282700 1832 ? Sl 03:50 0:03 /usr/local/apache2/bin/httpd -k start
daemon 3080 0.0 0.1 283724 2344 ? Sl 03:50 0:03 /usr/local/apache2/bin/httpd -k start
daemon 3081 0.0 0.1 283724 2332 ? Sl 03:50 0:03 /usr/local/apache2/bin/httpd -k start
root 5134 0.0 0.0 5980 732 pts/0 S+ 06:37 0:00 grep httpd
[root@weiyuan weiyuan]# kill -9 3078
[root@weiyuan weiyuan]# ps aux | grep httpd
daemon 3079 0.0 0.0 282700 1832 ? Sl 03:50 0:03 /usr/local/apache2/bin/httpd -k start
daemon 3080 0.0 0.1 283724 2344 ? Sl 03:50 0:03 /usr/local/apache2/bin/httpd -k start
daemon 3081 0.0 0.1 283724 2332 ? Sl 03:50 0:03 /usr/local/apache2/bin/httpd -k start
root 5136 0.0 0.0 5980 752 pts/0 S+ 06:37 0:00 grep httpd
[root@weiyuan weiyuan]#
要杀死全部的进程使用命令
[root@weiyuan weiyuan]# killall -9 httpd
[root@weiyuan weiyuan]# ps aux | grep httpd
root 5148 0.0 0.0 5980 732 pts/0 S+ 06:39 0:00 grep httpd
[root@weiyuan weiyuan]#
[root@weiyuan weiyuan]# nohup service httpd start &
[1] 5439
nohup 表示关闭了终端SecureCRT.exe的窗口进程不退出，&表示让进程在后台运行，所以nohup经常和&一起配合使用
读mysql数据引入redis缓存加快读的速度
缓冲用来加上写入硬盘的数据
[root@weiyuan weiyuan]# free -m
total used free shared buffers cached
Mem: 2194 397 1797 0 60 195
-/+ buffers/cache: 141 2053
Swap: 2335 0 2335
[root@weiyuan weiyuan]#
[root@weiyuan weiyuan]# chkconfig --list | grep httpd
httpd 0:关闭 1:关闭 2:启用 3:启用 4:启用 5:启用 6:关闭
[root@weiyuan weiyuan]# chkconfig --list | grep atd
atd 0:关闭 1:关闭 2:关闭 3:启用 4:启用 5:启用 6:关闭
[root@weiyuan weiyuan]#
[root@weiyuan weiyuan]# service atd status
atd (pid 1740) 正在运行...
系统中默认只存在at.deny文件，该文件默认的内容是null
[root@weiyuan weiyuan]# cd /etc/at.deny
bash: cd: /etc/at.deny: 不是目录
