Class: OsCtld::Lxcfs::Server

Inherits:
Object
  • Object
show all
Includes:
OsCtl::Lib::Utils::Log, OsCtl::Lib::Utils::System
Defined in:
lib/osctld/lxcfs/server.rb

Overview

Manage LXCFS instance using osctl-lxcfs runit service on the host

Constant Summary collapse

RUNDIR_SERVERS = 
File.join(RunState::LXCFS_DIR, 'servers')
RUNDIR_RUNSVDIR = 
File.join(RunState::LXCFS_DIR, 'runsvdir')
RUNDIR_MOUNTROOT = 
File.join(RunState::LXCFS_DIR, 'mountpoint')

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, uid: 0, gid: 0, mode: 0555, cpuset: nil, loadavg: true, cfs: true) ⇒ Server

Returns a new instance of Server.

Parameters:

  • name (String) —

    LXCFS instance name, used for runit service

  • uid (Integer) (defaults to: 0) —

    user ID with access to the mountpoint

  • gid (Integer) (defaults to: 0) —

    group ID with access to the mountpoint

  • mode (Integer) (defaults to: 0555) —

    mountpoint access mode

  • cpuset (String, nil) (defaults to: nil) —

    cpuset mask

  • loadavg (Boolean) (defaults to: true) —

    enable load average tracking

  • cfs (Boolean) (defaults to: true) —

    enable virtualized CPU usage view based on CFS quotas



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# File 'lib/osctld/lxcfs/server.rb', line 39

def initialize(name, uid: 0, gid: 0, mode: 0555, cpuset: nil, loadavg: true, cfs: true)
  @name = name
  @uid = uid
  @gid = gid
  @mode = mode
  @cpuset = cpuset
  @loadavg = loadavg
  @cfs = cfs
  @runsv_source = File.join(RUNDIR_SERVERS, name)
  @runsv_target = File.join(RUNDIR_RUNSVDIR, name)
  @runsv_run = File.join(runsv_source, 'run')
  @mountroot = File.join(RUNDIR_MOUNTROOT, name)
  @mountpoint = File.join(mountroot, 'mount')
  @cgroup_root = CGroup.abs_cgroup_path('cpuset', CGroup::ROOT_GROUP, 'lxcfs')
  @cgroup_dir = File.join(@cgroup_root, name)
end

Instance Attribute Details

#cfs ⇒ Boolean (readonly)

Returns:

  • (Boolean) 


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# File 'lib/osctld/lxcfs/server.rb', line 24

def cfs
  @cfs
end

#cgroup_dir ⇒ Object (readonly, protected)

Returns the value of attribute cgroup_dir.



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# File 'lib/osctld/lxcfs/server.rb', line 191

def cgroup_dir
  @cgroup_dir
end

#cgroup_root ⇒ Object (readonly, protected)

Returns the value of attribute cgroup_root.



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# File 'lib/osctld/lxcfs/server.rb', line 191

def cgroup_root
  @cgroup_root
end

#cpuset ⇒ String? (readonly)

Returns:

  • (String, nil) 


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# File 'lib/osctld/lxcfs/server.rb', line 18

def cpuset
  @cpuset
end

#gid ⇒ Object (readonly, protected)

Returns the value of attribute gid.



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# File 'lib/osctld/lxcfs/server.rb', line 191

def gid
  @gid
end

#loadavg ⇒ Boolean (readonly)

Returns:

  • (Boolean) 


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# File 'lib/osctld/lxcfs/server.rb', line 21

def loadavg
  @loadavg
end

#mode ⇒ Object (readonly, protected)

Returns the value of attribute mode.



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# File 'lib/osctld/lxcfs/server.rb', line 191

def mode
  @mode
end

#mountpoint ⇒ String (readonly)

Returns:

  • (String) 


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# File 'lib/osctld/lxcfs/server.rb', line 30

def mountpoint
  @mountpoint
end

#mountroot ⇒ String (readonly)

Returns:

  • (String) 


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# File 'lib/osctld/lxcfs/server.rb', line 27

def mountroot
  @mountroot
end

#name ⇒ String (readonly)

Returns:

  • (String) 


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# File 'lib/osctld/lxcfs/server.rb', line 15

def name
  @name
end

#runsv_run ⇒ Object (readonly, protected)

Returns the value of attribute runsv_run.



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# File 'lib/osctld/lxcfs/server.rb', line 191

def runsv_run
  @runsv_run
end

#runsv_source ⇒ Object (readonly, protected)

Returns the value of attribute runsv_source.



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# File 'lib/osctld/lxcfs/server.rb', line 191

def runsv_source
  @runsv_source
end

#runsv_target ⇒ Object (readonly, protected)

Returns the value of attribute runsv_target.



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# File 'lib/osctld/lxcfs/server.rb', line 191

def runsv_target
  @runsv_target
end

#uid ⇒ Object (readonly, protected)

Returns the value of attribute uid.



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# File 'lib/osctld/lxcfs/server.rb', line 191

def uid
  @uid
end

Instance Method Details

#chown(uid, gid) ⇒ Object

Change owner

Parameters:

  • uid (Integer)
  • gid (Integer) 


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# File 'lib/osctld/lxcfs/server.rb', line 127

def chown(uid, gid)
  @uid = uid
  @gid = gid

  begin
    File.chown(uid, gid, mountroot)
  rescue Errno::ENOENT
  end
end

#configure(loadavg: true, cfs: true) ⇒ Object 



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# File 'lib/osctld/lxcfs/server.rb', line 137

def configure(loadavg: true, cfs: true)
  @loadavg = loadavg
  @cfs = cfs
  create
end

#create ⇒ Object (protected) 



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# File 'lib/osctld/lxcfs/server.rb', line 212

def create
  cg_root = CGroup.abs_cgroup_path('cpuset', 'osctl')

  FileUtils.mkdir_p(runsv_source)
  ErbTemplate.render_to('ct/lxcfs_runsv', {
    executable: Daemon.get.config.lxcfs.path,
    name: name,
    cpuset: cpuset,
    cgroup_root: cgroup_root,
    cgroup_dir: cgroup_dir,
    options: options,
    mountpoint: mountpoint,
  }, runsv_run, perm: 0500)
end

#destroy ⇒ Object 



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# File 'lib/osctld/lxcfs/server.rb', line 86

def destroy
  log(:info, "Destroying LXCFS")
  FileUtils.rm_rf(runsv_source, secure: true)

  begin
    Dir.rmdir(mountpoint)
  rescue Errno::ENOENT
    # pass
  rescue SystemCallError => e
    log(
      :fatal,
      "Unable to delete LXCFS mountpoint at #{mountpoint}: #{e.message} (#{e.class})"
    )
  end

  begin
    Dir.rmdir(mountroot)
  rescue Errno::ENOENT
    # pass
  rescue SystemCallError => e
    log(
      :fatal,
      "Unable to delete LXCFS mountroot at #{mountroot}: #{e.message} (#{e.class})"
    )
  end

  begin
    Dir.rmdir(cgroup_dir)
  rescue Errno::ENOENT
    # pass
  rescue SystemCallError => e
    log(
      :fatal,
      "Unable to delete LXCFS cgroup at #{cgroup_dir}: #{e.message} (#{e.class})"
    )
  end
end

#ensure_destroy ⇒ Object

Stop and destroy LXCFS if it was created



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# File 'lib/osctld/lxcfs/server.rb', line 159

def ensure_destroy
  ensure_stop
  destroy if exist?
end

#ensure_start ⇒ Object

Start LXCFS if it is not already running



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# File 'lib/osctld/lxcfs/server.rb', line 148

def ensure_start
  start
  sv_command('start') if supervised?
end

#ensure_stop ⇒ Object

Stop LXCFS if it is running



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# File 'lib/osctld/lxcfs/server.rb', line 154

def ensure_stop
  stop if running?
end

#exist? ⇒ Boolean (protected)

Returns:

  • (Boolean) 


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# File 'lib/osctld/lxcfs/server.rb', line 194

def exist?
  File.exist?(runsv_run)
end

#log_type ⇒ Object 



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# File 'lib/osctld/lxcfs/server.rb', line 186

def log_type
  "lxcfs:#{name}"
end

#mount_files ⇒ Array<String>

Get a list of files which can be mounted from this LXCFS instance

Returns:

  • (Array<String>) 


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# File 'lib/osctld/lxcfs/server.rb', line 182

def mount_files
  Dir.glob('proc/*', base: mountpoint)
end

#operational? ⇒ Boolean (protected)

Returns:

  • (Boolean) 


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# File 'lib/osctld/lxcfs/server.rb', line 198

def operational?
  File.open(File.join(mountpoint, 'proc/cpuinfo')) do |f|
    f.readline
  end
  true

rescue SystemCallError
  false
end

#options ⇒ Object (protected) 



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# File 'lib/osctld/lxcfs/server.rb', line 227

def options
  ret = []
  ret << "--pidfile=#{File.join(runsv_source, 'lxcfs.pid')}"
  ret << '--enable-loadavg' if loadavg
  ret << '--enable-cfs' if cfs
  ret
end

#reconfigure ⇒ Object 



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# File 'lib/osctld/lxcfs/server.rb', line 143

def reconfigure
  create if exist?
end

#restart ⇒ Object 



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# File 'lib/osctld/lxcfs/server.rb', line 75

def restart
  log(:info, "Restarting LXCFS")
  sv_command('restart')
end

#running? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/osctld/lxcfs/server.rb', line 56

def running?
  Dir.exist?(runsv_target)
end

#start ⇒ Object 



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# File 'lib/osctld/lxcfs/server.rb', line 60

def start
  create unless exist?

  log(:info, "Starting LXCFS")

  FileUtils.mkdir_p(mountroot)
  File.chown(uid, gid, mountroot)
  File.chmod(mode, mountroot)

  begin
    File.symlink(runsv_source, runsv_target)
  rescue Errno::EEXIST
  end
end

#stop ⇒ Object 



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# File 'lib/osctld/lxcfs/server.rb', line 80

def stop
  log(:info, "Stopping LXCFS")
  sv_command('stop')
  File.unlink(runsv_target)
end

#supervised? ⇒ Boolean (protected)

Returns:

  • (Boolean) 


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# File 'lib/osctld/lxcfs/server.rb', line 208

def supervised?
  File.exist?(File.join(runsv_target, 'supervise/ok'))
end

#sv_command(command, timeout: 60) ⇒ Object (protected) 



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# File 'lib/osctld/lxcfs/server.rb', line 235

def sv_command(command, timeout: 60)
  syscmd("sv -w #{timeout} #{command} \"#{runsv_target}\"")
rescue SystemCommandFailed => e
  log(:warn, "sv #{command} failed: #{e.message}")
end

#wait(timeout: nil) ⇒ Object

Block until LXCFS becomes operational or timeout occurs

Raises:



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# File 'lib/osctld/lxcfs/server.rb', line 166

def wait(timeout: nil)
  wait_until = timeout && (Time.now + timeout)

  until operational?
    if timeout && wait_until < Time.now
      log(:fatal, 'Timed while waiting for LXCFS to become operational')
      raise Lxcfs::Timeout, "Timed out while waiting for LXCFS to become operational"
    end

    log(:info, 'Waiting for LXCFS to become operational')
    sleep(1)
  end
end