charm-neutron-openvswitch/hooks/charmhelpers/core/hugepage.py
2016-01-04 16:29:08 -05:00

72 lines
2.7 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2014-2015 Canonical Limited.
#
# This file is part of charm-helpers.
#
# charm-helpers is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License version 3 as
# published by the Free Software Foundation.
#
# charm-helpers is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>.
import yaml
from charmhelpers.core import fstab
from charmhelpers.core import sysctl
from charmhelpers.core.host import (
add_group,
add_user_to_group,
fstab_mount,
mkdir,
)
from charmhelpers.core.strutils import bytes_from_string
from subprocess import check_output
def hugepage_support(user, group='hugetlb', nr_hugepages=256,
max_map_count=65536, mnt_point='/run/hugepages/kvm',
pagesize='2MB', mount=True, set_shmmax=False):
"""Enable hugepages on system.
Args:
user (str) -- Username to allow access to hugepages to
group (str) -- Group name to own hugepages
nr_hugepages (int) -- Number of pages to reserve
max_map_count (int) -- Number of Virtual Memory Areas a process can own
mnt_point (str) -- Directory to mount hugepages on
pagesize (str) -- Size of hugepages
mount (bool) -- Whether to Mount hugepages
"""
group_info = add_group(group)
gid = group_info.gr_gid
add_user_to_group(user, group)
if max_map_count < 2 * nr_hugepages:
max_map_count = 2 * nr_hugepages
sysctl_settings = {
'vm.nr_hugepages': nr_hugepages,
'vm.max_map_count': max_map_count,
'vm.hugetlb_shm_group': gid,
}
if set_shmmax:
shmmax_current = int(check_output(['sysctl', '-n', 'kernel.shmmax']))
shmmax_minsize = bytes_from_string(pagesize) * nr_hugepages
if shmmax_minsize > shmmax_current:
sysctl_settings['kernel.shmmax'] = shmmax_minsize
sysctl.create(yaml.dump(sysctl_settings), '/etc/sysctl.d/10-hugepage.conf')
mkdir(mnt_point, owner='root', group='root', perms=0o755, force=False)
lfstab = fstab.Fstab()
fstab_entry = lfstab.get_entry_by_attr('mountpoint', mnt_point)
if fstab_entry:
lfstab.remove_entry(fstab_entry)
entry = lfstab.Entry('nodev', mnt_point, 'hugetlbfs',
'mode=1770,gid={},pagesize={}'.format(gid, pagesize), 0, 0)
lfstab.add_entry(entry)
if mount:
fstab_mount(mnt_point)