mirror of
https://github.com/scylladb/scylladb.git
synced 2026-06-03 21:47:10 +00:00
3fefa520bd
We initially implemented run() and out() functions because we couldn't use subprocess.run() since we were on Python 3.4. But since we moved to relocatable python3, we don't need to implement it ourselves. Why we keep using these functions are, because we needed to set environemnt variable to set PATH. Since we recently moved away these codes to python thunk, we finally able to drop run() and out(), switch to subprocess.run().
106 lines
3.6 KiB
Python
Executable File
106 lines
3.6 KiB
Python
Executable File
#!/usr/bin/env python3
|
|
# -*- coding: utf-8 -*-
|
|
#
|
|
# Copyright 2019 ScyllaDB
|
|
#
|
|
|
|
#
|
|
# This file is part of Scylla.
|
|
#
|
|
# Scylla is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU Affero General Public License as published by
|
|
# the Free Software Foundation, either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
#
|
|
# Scylla 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 General Public License for more details.
|
|
#
|
|
# You should have received a copy of the GNU General Public License
|
|
# along with Scylla. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
import os
|
|
import sys
|
|
import argparse
|
|
import psutil
|
|
from pathlib import Path
|
|
from scylla_util import *
|
|
from subprocess import run
|
|
|
|
def GB(n):
|
|
return n * 1024 * 1024 * 1024
|
|
|
|
def to_GB(n):
|
|
return '{:.2f}'.format(n / 1024 / 1024 / 1024)
|
|
|
|
if __name__ == '__main__':
|
|
if os.getuid() > 0:
|
|
print('Requires root permission.')
|
|
sys.exit(1)
|
|
parser = argparse.ArgumentParser(description='Configure swap for Scylla.')
|
|
parser.add_argument('--swap-directory',
|
|
help='specify swapfile directory', default='/')
|
|
parser.add_argument('--swap-size', type=int,
|
|
help='specify swapfile size in GB')
|
|
args = parser.parse_args()
|
|
|
|
if swap_exists():
|
|
print('swap already configured, exiting setup')
|
|
sys.exit(1)
|
|
|
|
diskfree = psutil.disk_usage(args.swap_directory).free
|
|
if args.swap_size:
|
|
swapsize = GB(args.swap_size)
|
|
if swapsize > diskfree:
|
|
print('swap directory {} does not have enough disk space. {}GB space required.'.format(args.swap_directory, to_GB(swapsize)))
|
|
sys.exit(1)
|
|
else:
|
|
memtotal = psutil.virtual_memory().total
|
|
|
|
# Scylla document says 'swap size should be set to either total_mem/3 or
|
|
# 16GB - lower of the two', so we need to compare 16g vs memtotal/3 and
|
|
# choose lower one
|
|
# see: https://docs.scylladb.com/faq/#do-i-need-to-configure-swap-on-a-scylla-node
|
|
swapsize = GB(16) if GB(16) < int(memtotal / 3) else int(memtotal / 3)
|
|
|
|
# We should not fill entire disk space with swapfile, it's safer to limit
|
|
# swap size 50% of diskfree
|
|
half_of_diskfree = int(diskfree / 2)
|
|
if swapsize > half_of_diskfree:
|
|
# out of disk space, abort setup
|
|
if half_of_diskfree <= GB(1):
|
|
print('swap directory {} does not have enough disk space.')
|
|
sys.exit(1)
|
|
swapsize = half_of_diskfree
|
|
|
|
swapsize_mb = int(swapsize / 1024 / 1024)
|
|
swapfile = Path(args.swap_directory) / 'swapfile'
|
|
if swapfile.exists():
|
|
print('swapfile {} already exists'.format(swapfile))
|
|
sys.exit(1)
|
|
run('dd if=/dev/zero of={} bs=1M count={}'.format(swapfile, swapsize_mb), shell=True, check=True)
|
|
swapfile.chmod(0o600)
|
|
run('mkswap -f {}'.format(swapfile), shell=True, check=True)
|
|
swapunit_bn = run('systemd-escape -p --suffix=swap {}'.format(swapfile), shell=True, check=True, capture_output=True, encoding='utf-8').stdout.strip()
|
|
swapunit = Path('/etc/systemd/system/{}'.format(swapunit_bn))
|
|
if swapunit.exists():
|
|
print('swap unit {} already exists'.format(swapunit))
|
|
sys.exit(1)
|
|
unit_data = '''
|
|
[Unit]
|
|
Description=swapfile
|
|
|
|
[Swap]
|
|
What={}
|
|
|
|
[Install]
|
|
WantedBy=multi-user.target
|
|
'''[1:-1].format(swapfile)
|
|
with swapunit.open('w') as f:
|
|
f.write(unit_data)
|
|
systemd_unit.reload()
|
|
swap = systemd_unit(swapunit_bn)
|
|
swap.enable()
|
|
swap.start()
|