root / lib / hypervisor / hv_base.py @ ddc64582
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#
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# Copyright (C) 2006, 2007, 2008, 2009, 2010, 2012, 2013 Google Inc.
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful, but
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# WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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# General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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# 02110-1301, USA.
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"""Base class for all hypervisors
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The syntax for the _CHECK variables and the contents of the PARAMETERS
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dict is the same, see the docstring for L{BaseHypervisor.PARAMETERS}.
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@var _FILE_CHECK: stub for file checks, without the required flag
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@var _DIR_CHECK: stub for directory checks, without the required flag
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@var REQ_FILE_CHECK: mandatory file parameter
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@var OPT_FILE_CHECK: optional file parameter
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@var REQ_DIR_CHECK: mandatory directory parametr
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@var OPT_DIR_CHECK: optional directory parameter
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@var NO_CHECK: parameter without any checks at all
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@var REQUIRED_CHECK: parameter required to exist (and non-false), but
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without other checks; beware that this can't be used for boolean
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parameters, where you should use NO_CHECK or a custom checker
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"""
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import os |
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import re |
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import logging |
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from ganeti import errors |
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from ganeti import utils |
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from ganeti import constants |
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def _IsCpuMaskWellFormed(cpu_mask): |
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"""Verifies if the given single CPU mask is valid
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The single CPU mask should be in the form "a,b,c,d", where each
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letter is a positive number or range.
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"""
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try:
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cpu_list = utils.ParseCpuMask(cpu_mask) |
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except errors.ParseError, _:
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return False |
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return isinstance(cpu_list, list) and len(cpu_list) > 0 |
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def _IsMultiCpuMaskWellFormed(cpu_mask): |
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"""Verifies if the given multiple CPU mask is valid
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A valid multiple CPU mask is in the form "a:b:c:d", where each
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letter is a single CPU mask.
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"""
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try:
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utils.ParseMultiCpuMask(cpu_mask) |
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except errors.ParseError, _:
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return False |
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return True |
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# Read the BaseHypervisor.PARAMETERS docstring for the syntax of the
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# _CHECK values
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# must be afile
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_FILE_CHECK = (utils.IsNormAbsPath, "must be an absolute normalized path",
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os.path.isfile, "not found or not a file")
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# must be a directory
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_DIR_CHECK = (utils.IsNormAbsPath, "must be an absolute normalized path",
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os.path.isdir, "not found or not a directory")
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# CPU mask must be well-formed
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# TODO: implement node level check for the CPU mask
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_CPU_MASK_CHECK = (_IsCpuMaskWellFormed, |
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"CPU mask definition is not well-formed",
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None, None) |
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# Multiple CPU mask must be well-formed
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_MULTI_CPU_MASK_CHECK = (_IsMultiCpuMaskWellFormed, |
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"Multiple CPU mask definition is not well-formed",
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None, None) |
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# Check for validity of port number
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_NET_PORT_CHECK = (lambda x: 0 < x < 65535, "invalid port number", |
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None, None) |
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# Check that an integer is non negative
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_NONNEGATIVE_INT_CHECK = (lambda x: x >= 0, "cannot be negative", None, None) |
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# nice wrappers for users
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REQ_FILE_CHECK = (True, ) + _FILE_CHECK
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OPT_FILE_CHECK = (False, ) + _FILE_CHECK
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REQ_DIR_CHECK = (True, ) + _DIR_CHECK
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OPT_DIR_CHECK = (False, ) + _DIR_CHECK
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REQ_NET_PORT_CHECK = (True, ) + _NET_PORT_CHECK
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OPT_NET_PORT_CHECK = (False, ) + _NET_PORT_CHECK
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REQ_CPU_MASK_CHECK = (True, ) + _CPU_MASK_CHECK
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OPT_CPU_MASK_CHECK = (False, ) + _CPU_MASK_CHECK
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REQ_MULTI_CPU_MASK_CHECK = (True, ) + _MULTI_CPU_MASK_CHECK
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OPT_MULTI_CPU_MASK_CHECK = (False, ) + _MULTI_CPU_MASK_CHECK
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REQ_NONNEGATIVE_INT_CHECK = (True, ) + _NONNEGATIVE_INT_CHECK
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OPT_NONNEGATIVE_INT_CHECK = (False, ) + _NONNEGATIVE_INT_CHECK
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# no checks at all
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NO_CHECK = (False, None, None, None, None) |
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# required, but no other checks
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REQUIRED_CHECK = (True, None, None, None, None) |
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# migration type
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MIGRATION_MODE_CHECK = (True, lambda x: x in constants.HT_MIGRATION_MODES, |
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"invalid migration mode", None, None) |
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def ParamInSet(required, my_set): |
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"""Builds parameter checker for set membership.
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@type required: boolean
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@param required: whether this is a required parameter
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@type my_set: tuple, list or set
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@param my_set: allowed values set
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"""
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fn = lambda x: x in my_set |
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err = ("The value must be one of: %s" % utils.CommaJoin(my_set))
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return (required, fn, err, None, None) |
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class BaseHypervisor(object): |
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"""Abstract virtualisation technology interface
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The goal is that all aspects of the virtualisation technology are
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abstracted away from the rest of code.
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@cvar PARAMETERS: a dict of parameter name: check type; the check type is
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a five-tuple containing:
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- the required flag (boolean)
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- a function to check for syntax, that will be used in
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L{CheckParameterSyntax}, in the master daemon process
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- an error message for the above function
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- a function to check for parameter validity on the remote node,
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in the L{ValidateParameters} function
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- an error message for the above function
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@type CAN_MIGRATE: boolean
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@cvar CAN_MIGRATE: whether this hypervisor can do migration (either
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live or non-live)
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"""
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PARAMETERS = {} |
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ANCILLARY_FILES = [] |
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ANCILLARY_FILES_OPT = [] |
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CAN_MIGRATE = False
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def StartInstance(self, instance, block_devices, startup_paused): |
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"""Start an instance."""
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raise NotImplementedError |
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def StopInstance(self, instance, force=False, retry=False, name=None, |
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timeout=None):
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"""Stop an instance
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@type instance: L{objects.Instance}
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@param instance: instance to stop
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@type force: boolean
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@param force: whether to do a "hard" stop (destroy)
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@type retry: boolean
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@param retry: whether this is just a retry call
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@type name: string or None
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@param name: if this parameter is passed, the the instance object
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should not be used (will be passed as None), and the shutdown
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must be done by name only
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@type timeout: int or None
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@param timeout: if the parameter is not None, a soft shutdown operation will
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be killed after the specified number of seconds. A hard (forced)
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shutdown cannot have a timeout
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"""
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raise NotImplementedError |
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def CleanupInstance(self, instance_name): |
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"""Cleanup after a stopped instance
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This is an optional method, used by hypervisors that need to cleanup after
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an instance has been stopped.
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@type instance_name: string
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@param instance_name: instance name to cleanup after
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"""
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pass
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def RebootInstance(self, instance): |
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"""Reboot an instance."""
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raise NotImplementedError |
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def ListInstances(self, hvparams=None): |
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"""Get the list of running instances."""
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raise NotImplementedError |
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def GetInstanceInfo(self, instance_name, hvparams=None): |
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"""Get instance properties.
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@type instance_name: string
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@param instance_name: the instance name
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@type hvparams: dict of strings
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@param hvparams: hvparams to be used with this instance
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@return: tuple (name, id, memory, vcpus, state, times)
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"""
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raise NotImplementedError |
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def GetAllInstancesInfo(self, hvparams=None): |
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"""Get properties of all instances.
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@type hvparams: dict of strings
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@param hvparams: hypervisor parameter
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@return: list of tuples (name, id, memory, vcpus, stat, times)
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"""
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raise NotImplementedError |
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def GetNodeInfo(self, hvparams=None): |
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"""Return information about the node.
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@type hvparams: dict of strings
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@param hvparams: hypervisor parameters
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@return: a dict with at least the following keys (memory values in MiB):
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- memory_total: the total memory size on the node
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- memory_free: the available memory on the node for instances
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- memory_dom0: the memory used by the node itself, if available
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- cpu_total: total number of CPUs
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- cpu_dom0: number of CPUs used by the node OS
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- cpu_nodes: number of NUMA domains
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- cpu_sockets: number of physical CPU sockets
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"""
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raise NotImplementedError |
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@classmethod
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def GetInstanceConsole(cls, instance, primary_node, hvparams, beparams): |
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"""Return information for connecting to the console of an instance.
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"""
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raise NotImplementedError |
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@classmethod
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def GetAncillaryFiles(cls): |
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"""Return a list of ancillary files to be copied to all nodes as ancillary
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configuration files.
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@rtype: (list of absolute paths, list of absolute paths)
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@return: (all files, optional files)
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"""
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# By default we return a member variable, so that if an hypervisor has just
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# a static list of files it doesn't have to override this function.
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assert set(cls.ANCILLARY_FILES).issuperset(cls.ANCILLARY_FILES_OPT), \ |
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"Optional ancillary files must be a subset of ancillary files"
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return (cls.ANCILLARY_FILES, cls.ANCILLARY_FILES_OPT)
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def Verify(self, hvparams=None): |
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"""Verify the hypervisor.
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@type hvparams: dict of strings
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@param hvparams: hypervisor parameters to be verified against
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@return: Problem description if something is wrong, C{None} otherwise
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"""
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raise NotImplementedError |
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def MigrationInfo(self, instance): # pylint: disable=R0201,W0613 |
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"""Get instance information to perform a migration.
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By default assume no information is needed.
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@type instance: L{objects.Instance}
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@param instance: instance to be migrated
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@rtype: string/data (opaque)
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@return: instance migration information - serialized form
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"""
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return "" |
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def AcceptInstance(self, instance, info, target): |
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"""Prepare to accept an instance.
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By default assume no preparation is needed.
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@type instance: L{objects.Instance}
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@param instance: instance to be accepted
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@type info: string/data (opaque)
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@param info: migration information, from the source node
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@type target: string
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@param target: target host (usually ip), on this node
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"""
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pass
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def BalloonInstanceMemory(self, instance, mem): |
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"""Balloon an instance memory to a certain value.
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@type instance: L{objects.Instance}
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@param instance: instance to be accepted
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@type mem: int
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@param mem: actual memory size to use for instance runtime
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"""
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raise NotImplementedError |
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def FinalizeMigrationDst(self, instance, info, success): |
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"""Finalize the instance migration on the target node.
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Should finalize or revert any preparation done to accept the instance.
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Since by default we do no preparation, we also don't have anything to do
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@type instance: L{objects.Instance}
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@param instance: instance whose migration is being finalized
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@type info: string/data (opaque)
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@param info: migration information, from the source node
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@type success: boolean
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@param success: whether the migration was a success or a failure
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"""
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pass
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def MigrateInstance(self, cluster_name, instance, target, live): |
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"""Migrate an instance.
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@type cluster_name: string
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@param cluster_name: name of the cluster
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@type instance: L{objects.Instance}
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@param instance: the instance to be migrated
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@type target: string
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@param target: hostname (usually ip) of the target node
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@type live: boolean
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@param live: whether to do a live or non-live migration
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"""
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raise NotImplementedError |
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def FinalizeMigrationSource(self, instance, success, live): |
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"""Finalize the instance migration on the source node.
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@type instance: L{objects.Instance}
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@param instance: the instance that was migrated
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@type success: bool
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@param success: whether the migration succeeded or not
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@type live: bool
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@param live: whether the user requested a live migration or not
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"""
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pass
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def GetMigrationStatus(self, instance): |
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"""Get the migration status
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@type instance: L{objects.Instance}
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@param instance: the instance that is being migrated
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@rtype: L{objects.MigrationStatus}
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@return: the status of the current migration (one of
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L{constants.HV_MIGRATION_VALID_STATUSES}), plus any additional
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progress info that can be retrieved from the hypervisor
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"""
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raise NotImplementedError |
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def _InstanceStartupMemory(self, instance): |
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"""Get the correct startup memory for an instance
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This function calculates how much memory an instance should be started
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with, making sure it's a value between the minimum and the maximum memory,
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but also trying to use no more than the current free memory on the node.
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@type instance: L{objects.Instance}
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@param instance: the instance that is being started
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@rtype: integer
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@return: memory the instance should be started with
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"""
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free_memory = self.GetNodeInfo(hvparams=instance.hvparams)["memory_free"] |
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max_start_mem = min(instance.beparams[constants.BE_MAXMEM], free_memory)
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start_mem = max(instance.beparams[constants.BE_MINMEM], max_start_mem)
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return start_mem
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@classmethod
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def CheckParameterSyntax(cls, hvparams): |
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"""Check the given parameters for validity.
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This should check the passed set of parameters for
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validity. Classes should extend, not replace, this function.
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@type hvparams: dict
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@param hvparams: dictionary with parameter names/value
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@raise errors.HypervisorError: when a parameter is not valid
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"""
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for key in hvparams: |
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if key not in cls.PARAMETERS: |
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raise errors.HypervisorError("Parameter '%s' is not supported" % key) |
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# cheap tests that run on the master, should not access the world
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for name, (required, check_fn, errstr, _, _) in cls.PARAMETERS.items(): |
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if name not in hvparams: |
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raise errors.HypervisorError("Parameter '%s' is missing" % name) |
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value = hvparams[name] |
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if not required and not value: |
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continue
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if not value: |
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raise errors.HypervisorError("Parameter '%s' is required but" |
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" is currently not defined" % (name, ))
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if check_fn is not None and not check_fn(value): |
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raise errors.HypervisorError("Parameter '%s' fails syntax" |
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" check: %s (current value: '%s')" %
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(name, errstr, value)) |
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@classmethod
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def ValidateParameters(cls, hvparams): |
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"""Check the given parameters for validity.
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This should check the passed set of parameters for
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validity. Classes should extend, not replace, this function.
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@type hvparams: dict
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@param hvparams: dictionary with parameter names/value
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@raise errors.HypervisorError: when a parameter is not valid
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"""
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for name, (required, _, _, check_fn, errstr) in cls.PARAMETERS.items(): |
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value = hvparams[name] |
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if not required and not value: |
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continue
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if check_fn is not None and not check_fn(value): |
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raise errors.HypervisorError("Parameter '%s' fails" |
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" validation: %s (current value: '%s')" %
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(name, errstr, value)) |
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@classmethod
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def PowercycleNode(cls, hvparams=None): |
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"""Hard powercycle a node using hypervisor specific methods.
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This method should hard powercycle the node, using whatever
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methods the hypervisor provides. Note that this means that all
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instances running on the node must be stopped too.
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@type hvparams: dict of strings
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@param hvparams: hypervisor params to be used on this node
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"""
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raise NotImplementedError |
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@staticmethod
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def GetLinuxNodeInfo(meminfo="/proc/meminfo", cpuinfo="/proc/cpuinfo"): |
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"""For linux systems, return actual OS information.
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This is an abstraction for all non-hypervisor-based classes, where
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the node actually sees all the memory and CPUs via the /proc
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interface and standard commands. The other case if for example
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xen, where you only see the hardware resources via xen-specific
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tools.
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@param meminfo: name of the file containing meminfo
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@type meminfo: string
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@param cpuinfo: name of the file containing cpuinfo
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@type cpuinfo: string
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@return: a dict with the following keys (values in MiB):
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- memory_total: the total memory size on the node
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- memory_free: the available memory on the node for instances
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- memory_dom0: the memory used by the node itself, if available
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- cpu_total: total number of CPUs
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- cpu_dom0: number of CPUs used by the node OS
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- cpu_nodes: number of NUMA domains
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- cpu_sockets: number of physical CPU sockets
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"""
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try:
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data = utils.ReadFile(meminfo).splitlines() |
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except EnvironmentError, err: |
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raise errors.HypervisorError("Failed to list node info: %s" % (err,)) |
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result = {} |
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sum_free = 0
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try:
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for line in data: |
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splitfields = line.split(":", 1) |
507 |
|
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if len(splitfields) > 1: |
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key = splitfields[0].strip()
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val = splitfields[1].strip()
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if key == "MemTotal": |
512 |
result["memory_total"] = int(val.split()[0]) / 1024 |
513 |
elif key in ("MemFree", "Buffers", "Cached"): |
514 |
sum_free += int(val.split()[0]) / 1024 |
515 |
elif key == "Active": |
516 |
result["memory_dom0"] = int(val.split()[0]) / 1024 |
517 |
except (ValueError, TypeError), err: |
518 |
raise errors.HypervisorError("Failed to compute memory usage: %s" % |
519 |
(err,)) |
520 |
result["memory_free"] = sum_free
|
521 |
|
522 |
cpu_total = 0
|
523 |
try:
|
524 |
fh = open(cpuinfo)
|
525 |
try:
|
526 |
cpu_total = len(re.findall(r"(?m)^processor\s*:\s*[0-9]+\s*$", |
527 |
fh.read())) |
528 |
finally:
|
529 |
fh.close() |
530 |
except EnvironmentError, err: |
531 |
raise errors.HypervisorError("Failed to list node info: %s" % (err,)) |
532 |
result["cpu_total"] = cpu_total
|
533 |
# We assume that the node OS can access all the CPUs
|
534 |
result["cpu_dom0"] = cpu_total
|
535 |
# FIXME: export correct data here
|
536 |
result["cpu_nodes"] = 1 |
537 |
result["cpu_sockets"] = 1 |
538 |
|
539 |
return result
|
540 |
|
541 |
@classmethod
|
542 |
def LinuxPowercycle(cls): |
543 |
"""Linux-specific powercycle method.
|
544 |
|
545 |
"""
|
546 |
try:
|
547 |
fd = os.open("/proc/sysrq-trigger", os.O_WRONLY)
|
548 |
try:
|
549 |
os.write(fd, "b")
|
550 |
finally:
|
551 |
fd.close() |
552 |
except OSError: |
553 |
logging.exception("Can't open the sysrq-trigger file")
|
554 |
result = utils.RunCmd(["reboot", "-n", "-f"]) |
555 |
if not result: |
556 |
logging.error("Can't run shutdown: %s", result.output)
|
557 |
|
558 |
@staticmethod
|
559 |
def _FormatVerifyResults(msgs): |
560 |
"""Formats the verification results, given a list of errors.
|
561 |
|
562 |
@param msgs: list of errors, possibly empty
|
563 |
@return: overall problem description if something is wrong,
|
564 |
C{None} otherwise
|
565 |
|
566 |
"""
|
567 |
if msgs:
|
568 |
return "; ".join(msgs) |
569 |
else:
|
570 |
return None |