禁用透明HugePages

1.檢查是否已啟用Transparent HugePages
紅帽企業Linux內核：

#?cat?/sys/kernel/mm/redhat_transparent_hugepage/enabled

其他內核：

#?cat?/sys/kernel/mm/transparent_hugepage/enabled
[always]?madvise?never??<<----?[always]標志?THP?is?enabled?
如果從內核中刪除Transparent?HugePages，則既不存在/sys/kernel/mm/transparent_hugepage
也不/sys/kernel/mm/redhat_transparent_hugepage?files存在。

2.禁用透明HugePages：

OL 7：

1.編輯tuned.conf
[root@prodb?~]#?uname?-r
4.1.12-112.16.4.el7uek.x86_64
[root@prodb?~]#?cat?/sys/kernel/mm/transparent_hugepage/enabled?
always?madvise?[never]

[root@prodb?~]#?cd?/usr/lib/tuned/throughput-performance/
[root@prodb?~]#?cp?tuned.conf?tuned.conf.bak
[vm]
?transparent_hugepages=always
?to?
[vm]
transparent_hugepages=never
2.重啟
#?shutdown?-r?now
3.校驗
[root@prodb?~]#?uname?-r
4.1.12-112.16.4.el7uek.x86_64
[root@prodb?~]#?cat?/sys/kernel/mm/transparent_hugepage/enabled?
always?madvise?[never]??<<---?THP?Disabled
#?cat?/proc/cmdline
BOOT_IMAGE=/vmlinuz-4.1.12-112.16.4.el7uek.x86_64?....?transparent_hugepage=never
如果未生效，按如下方法設置：
1.檢查profile
#?tuned-adm?active
Current?active?profile:?virtual-guest?<<---?Virtual-guest?is?the?active?profile
2.修改tuned.conf
#cp?/usr/lib/tuned/virtual-guest/tuned.conf?/usr/lib/tuned/virtual-guest/tuned.conf.bkp_original
增加以下內容：
[main]
include=throughput-performance
[vm]
transparent_hugepages=never
3.重啟
#?shutdown?-r?now
4.校驗
[root@prodb?~]#?uname?-r
[root@prodb?~]#?cat?/sys/kernel/mm/transparent_hugepage/enabled?
#?cat?/proc/cmdline

RHEL 7:

1.編輯grub.conf
在GRUB_CMDLINE_LINUX末尾添加transparent_hugepage=never?
#vim?/etc/default/grub
GRUB_CMDLINE_LINUX="rd.lvm.lv=rhel/root?rd.lvm.lv=rhel/swap?...?transparent_hugepage=never"
2.Rebuild?grub
On?BIOS-based?machines:?~]#?grub2-mkconfig?-o?/boot/grub2/grub.cfg
On?UEFI-based?machines:?~]#?grub2-mkconfig?-o?/boot/efi/EFI/redhat/grub.cfg
3.reboot
#?shutdown?-r?now
4.校驗
#?cat?/proc/cmdline
BOOT_IMAGE=/vmlinuz-4.1.12-112.16.4.el7uek.x86_64?....?transparent_hugepage=never
如果未生效，按如下方法設置：
1.檢查profile
#?tuned-adm?active
2.自定義profile
#?mkdir?/etc/tuned/myprofile-nothp
#?cat?/etc/tuned/myprofile-nothp/tuned.conf
[main]
include=?throughput-performance
[vm]
transparent_hugepages=never
3.激活配置文件
#?chmod?+x?/etc/tuned/myprofile-nothp/tuned.conf
#?tuned-adm?profile?myprofile-nothp
4.重啟校驗
#?shutdown?-r?now
#?cat?/sys/kernel/mm/transparent_hugepage/enabled
5.關閉服務
#?systemctl?stop?tuned
#?systemctl?disable?tuned
#?systemctl?stop?ktune
#?systemctl?disable?ktune
或者
#?tuned-adm?off
THP?status?in?other?UEK?kernel?versions
UEK3?disabled?by?default??
[root@ol6?~]#?grep?-i?CONFIG_TRANSPARENT_HUGEPAGE?/boot/config-3.8.13-118.6.2.el6uek.x86_64
#?CONFIG_TRANSPARENT_HUGEPAGE?is?not?set??
UEK4?enabled?by?default
[root@ol7?~]#?grep?-i?CONFIG_TRANSPARENT_HUGEPAGE?/boot/config-4.1.12-37.2.2.el7uek.x86_64
CONFIG_TRANSPARENT_HUGEPAGE=y
CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS=y

RHEL 6或更低版本

啟用狀態為[always]
#?cat?/sys/kernel/mm/[hedhat_]transparent_hugepage/enabled
[always]?never
或者查詢以下內容
#?grep?AnonHugePages?/proc/meminfo
AnonHugepages:?xxxx?kB
要求XXXX>0
禁用狀態為[never]
#?cat?/sys/kernel/mm/[hedhat_]transparent_hugepage/enabled
always?[never]
禁用huge
1.編輯grub.conf?
#vi??/etc/grub.conf?
kernel?/vmlinuz-2.6.32-300.25.1.el6uek.x86_64?ro?root=LABEL=/?transparent_hugepage=never
或者
#vi?/etc/rc.local
if?test?-f?/sys/kernel/mm/transparent_hugepage/enabled;?then
???echo?never?>?/sys/kernel/mm/transparent_hugepage/enabled
fi
if?test?-f?/sys/kernel/mm/transparent_hugepage/defrag;?then
???echo?never?>?/sys/kernel/mm/transparent_hugepage/defrag
fi
2.重啟生效

引用：

ALERT:?Disable?Transparent?HugePages?on?SLES11,?RHEL6,?RHEL7,?OL6,?OL7,?and?UEK2?and?above?(文檔?ID?1557478.1)??
NOTE:2066217.1?-?Oracle?Linux?7?-?How?to?disable?Transparent?HugePages?for?RHCK?kernel???
(How?to?disable?transparent?hugepages?(THP)?on?Red?Hat?Enterprise?Linux?7)