pvc/node-daemon/pvcd/common.py

261 lines
8.1 KiB
Python

#!/usr/bin/env python3
# common.py - PVC daemon function library, common fuctions
# Part of the Parallel Virtual Cluster (PVC) system
#
# Copyright (C) 2018-2020 Joshua M. Boniface <joshua@boniface.me>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
#
###############################################################################
import subprocess
import threading
import signal
import os
import time
import shlex
import pvcd.log as log
import pvcd.zkhandler as zkhandler
class OSDaemon(object):
def __init__(self, command_string, environment, logfile):
command = shlex.split(command_string)
# Set stdout to be a logfile if set
if logfile:
stdout = open(logfile, 'a')
else:
stdout = subprocess.PIPE
# Invoke the process
self.proc = subprocess.Popen(
command,
env=environment,
stdout=stdout,
stderr=stdout,
)
# Signal the process
def signal(self, sent_signal):
signal_map = {
'hup': signal.SIGHUP,
'int': signal.SIGINT,
'term': signal.SIGTERM,
'kill': signal.SIGKILL
}
self.proc.send_signal(signal_map[sent_signal])
def run_os_daemon(command_string, environment=None, logfile=None):
daemon = OSDaemon(command_string, environment, logfile)
return daemon
# Run a oneshot command, optionally without blocking
def run_os_command(command_string, background=False, environment=None, timeout=None):
command = shlex.split(command_string)
if background:
def runcmd():
try:
subprocess.run(
command,
env=environment,
timeout=timeout,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
)
except subprocess.TimeoutExpired:
pass
thread = threading.Thread(target=runcmd, args=())
thread.start()
return 0, None, None
else:
try:
command_output = subprocess.run(
command,
env=environment,
timeout=timeout,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
)
retcode = command_output.returncode
except subprocess.TimeoutExpired:
retcode = 128
try:
stdout = command_output.stdout.decode('ascii')
except:
stdout = ''
try:
stderr = command_output.stderr.decode('ascii')
except:
stderr = ''
return retcode, stdout, stderr
# Reload the firewall rules of the system
def reload_firewall_rules(logger, rules_file):
logger.out('Reloading firewall configuration', state='o')
retcode, stdout, stderr = run_os_command('/usr/sbin/nft -f {}'.format(rules_file))
if retcode != 0:
logger.out('Failed to reload configuration: {}'.format(stderr), state='e')
# Create IP address
def createIPAddress(ipaddr, cidrnetmask, dev):
run_os_command(
'ip address add {}/{} dev {}'.format(
ipaddr,
cidrnetmask,
dev
)
)
run_os_command(
'arping -P -U -W 0.02 -c 2 -i {dev} -S {ip} {ip}'.format(
dev=dev,
ip=ipaddr
)
)
# Remove IP address
def removeIPAddress(ipaddr, cidrnetmask, dev):
run_os_command(
'ip address delete {}/{} dev {}'.format(
ipaddr,
cidrnetmask,
dev
)
)
#
# Find a migration target
#
def findTargetNode(zk_conn, config, dom_uuid):
# Determine VM node limits; set config value if read fails
try:
node_limit = zkhandler.readdata(zk_conn, '/domains/{}/node_limit'.format(dom_uuid)).split(',')
if not any(node_limit):
node_limit = ''
except:
node_limit = ''
zkhandler.writedata(zk_conn, { '/domains/{}/node_limit'.format(dom_uuid): '' })
# Determine VM search field
try:
search_field = zkhandler.readdata(zk_conn, '/domains/{}/node_selector'.format(dom_uuid))
except Exception as e:
search_field = None
# If our search field is invalid, use and set the default (for next time)
if search_field is None or search_field == 'None':
search_field = config['migration_target_selector']
zkhandler.writedata(zk_conn, { '/domains/{}/node_selector'.format(dom_uuid): config['migration_target_selector'] })
# Execute the search
if search_field == 'mem':
return findTargetNodeMem(zk_conn, node_limit, dom_uuid)
if search_field == 'load':
return findTargetNodeLoad(zk_conn, node_limit, dom_uuid)
if search_field == 'vcpus':
return findTargetNodeVCPUs(zk_conn, node_limit, dom_uuid)
if search_field == 'vms':
return findTargetNodeVMs(zk_conn, node_limit, dom_uuid)
# Nothing was found
return None
# Get the list of valid target nodes
def getNodes(zk_conn, node_limit, dom_uuid):
valid_node_list = []
full_node_list = zkhandler.listchildren(zk_conn, '/nodes')
current_node = zkhandler.readdata(zk_conn, '/domains/{}/node'.format(dom_uuid))
for node in full_node_list:
if node_limit and node not in node_limit:
continue
daemon_state = zkhandler.readdata(zk_conn, '/nodes/{}/daemonstate'.format(node))
domain_state = zkhandler.readdata(zk_conn, '/nodes/{}/domainstate'.format(node))
if node == current_node:
continue
if daemon_state != 'run' or domain_state != 'ready':
continue
valid_node_list.append(node)
return valid_node_list
# via free memory (relative to allocated memory)
def findTargetNodeMem(zk_conn, node_limit, dom_uuid):
most_allocfree = 0
target_node = None
node_list = getNodes(zk_conn, node_limit, dom_uuid)
for node in node_list:
memalloc = int(zkhandler.readdata(zk_conn, '/nodes/{}/memalloc'.format(node)))
memused = int(zkhandler.readdata(zk_conn, '/nodes/{}/memused'.format(node)))
memfree = int(zkhandler.readdata(zk_conn, '/nodes/{}/memfree'.format(node)))
memtotal = memused + memfree
allocfree = memtotal - memalloc
if allocfree > most_allocfree:
most_allocfree = allocfree
target_node = node
return target_node
# via load average
def findTargetNodeLoad(zk_conn, node_limit, dom_uuid):
least_load = 9999.0
target_node = None
node_list = getNodes(zk_conn, node_limit, dom_uuid)
for node in node_list:
load = float(zkhandler.readdata(zk_conn, '/nodes/{}/cpuload'.format(node)))
if load < least_load:
least_load = load
target_node = node
return target_node
# via total vCPUs
def findTargetNodeVCPUs(zk_conn, node_limit, dom_uuid):
least_vcpus = 9999
target_node = None
node_list = getNodes(zk_conn, node_limit, dom_uuid)
for node in node_list:
vcpus = int(zkhandler.readdata(zk_conn, '/nodes/{}/vcpualloc'.format(node)))
if vcpus < least_vcpus:
least_vcpus = vcpus
target_node = node
return target_node
# via total VMs
def findTargetNodeVMs(zk_conn, node_limit, dom_uuid):
least_vms = 9999
target_node = None
node_list = getNodes(zk_conn, node_limit, dom_uuid)
for node in node_list:
vms = int(zkhandler.readdata(zk_conn, '/nodes/{}/domainscount'.format(node)))
if vms < least_vms:
least_vms = vms
target_node = node
return target_node