rhel7.6 尝鲜

郑全

2018年10月30日发布，11月1日晚上下载，已经于11月1日晚上 10点安装完毕。


[root@dbserver setup]# cat /etc/redhat-release
Red Hat Enterprise Linux Server release 7.6 (Maipo)
[root@dbserver setup]# uname -r
3.10.0-957.el7.x86_64
[root@dbserver setup]#


先安装起再说，安装上没有任何变化，后续继续探索。

郑全

卸载虚拟网桥：

[root@dbserver yum.repos.d]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.133.129  netmask 255.255.255.0  broadcast 192.168.133.255
        inet6 fe80::4a8e:4036:af1f:9458  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:c9:d9:6d  txqueuelen 1000  (Ethernet)
        RX packets 5558507  bytes 8005462038 (7.4 GiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 395468  bytes 86772485 (82.7 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 32  bytes 2528 (2.4 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 32  bytes 2528 (2.4 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

virbr0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        inet 192.168.122.1  netmask 255.255.255.0  broadcast 192.168.122.255
        ether 52:54:00:0f:57:c0  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

卸载  virbr0

yum remove libvirt-libs.x86_64

之后，重启。

[root@dbserver ~]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.133.129  netmask 255.255.255.0  broadcast 192.168.133.255
        inet6 fe80::4a8e:4036:af1f:9458  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:c9:d9:6d  txqueuelen 1000  (Ethernet)
        RX packets 72  bytes 8853 (8.6 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 98  bytes 14227 (13.8 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 32  bytes 2528 (2.4 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 32  bytes 2528 (2.4 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

[root@dbserver ~]#

已经没有virtbr0了。

郑全

关闭透明大页内存：

1.查看目前默认情况

[root@dbserver ~]# cat /sys/kernel/mm/transparent_hugepage/enabled
[always] madvise never
[root@dbserver ~]#
看来是开启的

2.修改内核启动选项
  vim  /etc/default/grub
  ...
  GRUB_CMDLINE_LINUX="rd.lvm.lv=rhel/root rd.lvm.lv=rhel/swap ... transparent_hugepage=never"

3.重建启动菜单
  grub2-mkconfig -o /boot/grub2/grub.cfg

。。。
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-3.10.0-957.el7.x86_64
Found initrd image: /boot/initramfs-3.10.0-957.el7.x86_64.img
Found linux image: /boot/vmlinuz-0-rescue-26efdcc83a1e41679614c0a19f381de5
Found initrd image: /boot/initramfs-0-rescue-26efdcc83a1e41679614c0a19f381de5.img


4.重启验证
  [root@dbserver ~]# cat /sys/kernel/mm/transparent_hugepage/enabled
always madvise [never]