如何给redhat系统(RHEL9.4)配置Hugepage

因为目前在openshift的容器里使用hugepage， 不能使用iova-mode:pa 模式， 我需要判断底层的redhat 系统上能不能使用hugepage。 如果RHEL能使用， 那就是openshift 上层平台阻止了Hugepage的使用。

从网上找了几个链接配置都没有成功。

无意中在查看OS 版本时， 看到了文档说明 ：

[root@localhost testmacDemo]# cat /etc/os-release
NAME="Red Hat Enterprise Linux"
VERSION="9.4 (Plow)"
ID="rhel"
ID_LIKE="fedora"
VERSION_ID="9.4"
PLATFORM_ID="platform:el9"
PRETTY_NAME="Red Hat Enterprise Linux 9.4 (Plow)"
ANSI_COLOR="0;31"
LOGO="fedora-logo-icon"
CPE_NAME="cpe:/o:redhat:enterprise_linux:9::baseos"
HOME_URL="https://www.redhat.com/"
DOCUMENTATION_URL="https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/9"
BUG_REPORT_URL="https://issues.redhat.com/"

REDHAT_BUGZILLA_PRODUCT="Red Hat Enterprise Linux 9"
REDHAT_BUGZILLA_PRODUCT_VERSION=9.4
REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux"
REDHAT_SUPPORT_PRODUCT_VERSION="9.4"

这不就有希望了， 按照说明， 搞了几次成功了。 步骤分享如下：

1.To create a HugeTLB pool for 1 GB pages, enable the default_hugepagesz=1G and hugepagesz=1G kernel options:
grubby --update-kernel=ALL --args="default_hugepagesz=1G hugepagesz=1G"

2.Create a new file called hugetlb-gigantic-pages.service in the /usr/lib/systemd/system/ directory and add the following content:

[Unit]
Description=HugeTLB Gigantic Pages Reservation
DefaultDependencies=no
Before=dev-hugepages.mount
ConditionPathExists=/sys/devices/system/node
ConditionKernelCommandLine=hugepagesz=1G

[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/usr/lib/systemd/hugetlb-reserve-pages.sh

[Install]
WantedBy=sysinit.target

3.Create a new file called hugetlb-reserve-pages.sh in the /usr/lib/systemd/ directory and add the following content:

While adding the following content, replace number_of_pages with the number of 1GB pages you want to reserve, and node with the name of the node on which to reserve these pages.

#!/bin/sh

nodes_path=/sys/devices/system/node/
if [ ! -d $nodes_path ]; then
    echo "ERROR: $nodes_path does not exist"
    exit 1
fi

reserve_pages()
{
    echo $1 > $nodes_path/$2/hugepages/hugepages-1048576kB/nr_hugepages
}

reserve_pages 8 node0
reserve_pages 8 node1

4.Create an executable script:
chmod +x /usr/lib/systemd/hugetlb-reserve-pages.sh

5. Enable early boot reservation:
systemctl enable hugetlb-gigantic-pages

6. reboot.
7.Password:
[root@localhost test]# cat /proc/meminfo
MemTotal:       63864348 kB
MemFree:        44422116 kB
MemAvailable:   44692992 kB
Buffers:            5012 kB
Cached:           750512 kB
SwapCached:            0 kB
Active:          1203648 kB
Inactive:         352900 kB
Active(anon):     849800 kB
Inactive(anon):        0 kB
Active(file):     353848 kB
Inactive(file):   352900 kB
Unevictable:          96 kB
Mlocked:               0 kB
SwapTotal:      24420348 kB
SwapFree:       24420348 kB
Zswap:                 0 kB
Zswapped:              0 kB
Dirty:                20 kB
Writeback:             0 kB
AnonPages:        789012 kB
Mapped:           241468 kB
Shmem:             48772 kB
KReclaimable:      57988 kB
Slab:             228168 kB
SReclaimable:      57988 kB
SUnreclaim:       170180 kB
KernelStack:       20048 kB
PageTables:        17180 kB
SecPageTables:         0 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:    47963912 kB
Committed_AS:    4607012 kB
VmallocTotal:   133141626880 kB
VmallocUsed:      180244 kB
VmallocChunk:          0 kB
Percpu:            69888 kB
HardwareCorrupted:     0 kB
AnonHugePages:    116736 kB
ShmemHugePages:        0 kB
ShmemPmdMapped:        0 kB
FileHugePages:         0 kB
FilePmdMapped:         0 kB
CmaTotal:              0 kB
CmaFree:               0 kB
HugePages_Total:      16
HugePages_Free:       16
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:    1048576 kB
Hugetlb:        16777216 kB