[pve-devel] [PATCH 1/2] add hugepages option

[Alexandre DERUMIER]

>>who mount that?

# mount|grep hugecgroup on /sys/fs/cgroup/hugetlb type cgroup
(rw,nosuid,nodev,noexec,relatime,hugetlb,release_agent=/run/cgmanager/agents/cgm-release-agent.hugetlb,nsroot=/)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime)

cgmanager.service


>>hugetlb on /run/lxcfs/controllers/hugetlb type cgroup
>>(rw,relatime,hugetlb,release_agent=/run/cgmanager/agents/cgm-release-agent.hugetlb,nsroot=/)

lxcfs.service


so we have already a default hugetlbfs of 2MB in /dev/hugepages

For 1GB, we can define another mount point


openstack use

2M : /run/hugepages/kvm
1G : /run/hugepages/kvm_1GB

for example

(It's possible to have /dev/hugepages and /run/hugepages/kvm  at the same time, as the files are allocated by process using pages, so they are no conflict)




----- Mail original -----
De: "dietmar" <dietmar at proxmox.com>
À: "aderumier" <aderumier at odiso.com>, "pve-devel" <pve-devel at pve.proxmox.com>
Envoyé: Jeudi 12 Mai 2016 12:57:42
Objet: Re: [pve-devel] [PATCH 1/2] add hugepages option

> host configuration 
> ------------------ 
> hugepages need to be allocated at boot 
> 
> for 4GB of 2M hugepages 
> 
> /etc/default/grub 
> ----------------- 
> GRUB_CMDLINE_LINUX_DEFAULT="quiet hugepagesz=2M hugepages=2048" 
> 
> /etc/fstab 
> ---------- 
> hugetlbfs /dev/hugepages hugetlbfs pagesize=2048k 0 0 
> 
> for 4GB for 1GB hugepages 
> 
> /etc/default/grub 
> ----------------- 
> GRUB_CMDLINE_LINUX_DEFAULT="quiet default_hugepagesz=1G hugepagesz=1G 
> hugepages=4" 

It is still unclear to me how to setup hugepages. On my host /dev/hugepages 
is already mounted: 

# mount|grep hugecgroup on /sys/fs/cgroup/hugetlb type cgroup 
(rw,nosuid,nodev,noexec,relatime,hugetlb,release_agent=/run/cgmanager/agents/cgm-release-agent.hugetlb,nsroot=/) 
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime) 
hugetlb on /run/lxcfs/controllers/hugetlb type cgroup 
(rw,relatime,hugetlb,release_agent=/run/cgmanager/agents/cgm-release-agent.hugetlb,nsroot=/) 

who mount that? Do I still need above setup? How do I know the number 
of required hugepages in advance? How can we make that more convenient for 
the user?