[Kimchi-devel] [PATCH v1] Parts to allow Kimchi to configure the cpu topology.
Aline Manera
alinefm at linux.vnet.ibm.com
Mon Nov 3 19:08:59 UTC 2014
By default, Kimchi always sets the best Template configuration for user
based on a single input: ISO file or Image file.
So you don't need to create an API (auto-topology) for it. It will be
the default behavior.
The flow is:
- Create a Template which will get the default CPU topology according to
host OS and ISO OS.
POST /templates {name: my-tmpl, cdrom: <my-iso>}
- Update the CPU topology according to your needs:
PUT /templates/my-tmpl {cpu_info: {...}}
Ok?
See more comments inline below:
On 11/03/2014 12:36 AM, Christy Perez wrote:
> Signed-off-by: Christy Perez <christy at linux.vnet.ibm.com>
> ---
> docs/API.md | 2 +
> src/kimchi/API.json | 6 ++
> src/kimchi/control/cpuinfo.py | 37 +++++++++
> src/kimchi/i18n.py | 2 +
> src/kimchi/model/cpuinfo.py | 176 ++++++++++++++++++++++++++++++++++++++++++
> src/kimchi/model/host.py | 1 +
> src/kimchi/model/templates.py | 13 +++-
> 7 files changed, 236 insertions(+), 1 deletion(-)
> create mode 100644 src/kimchi/control/cpuinfo.py
> create mode 100644 src/kimchi/model/cpuinfo.py
-----
> diff --git a/docs/API.md b/docs/API.md
> index 9c06f85..4e449b3 100644
> --- a/docs/API.md
> +++ b/docs/API.md
> @@ -226,6 +226,8 @@ Represents a snapshot of the Virtual Machine's primary monitor.
> * threads - The number of threads per core.
> If specifying both cpus and CPU topology, make sure cpus is
> equal to the product of sockets, cores, and threads.
> + * auto-topology: Allow Kimchi to determine the best topology
> + based on desired vCPUs and host capabilities.
>
> ### Sub-Collection: Virtual Machine Network Interfaces
>
> diff --git a/src/kimchi/API.json b/src/kimchi/API.json
> index 0ad36ab..b405889 100644
> --- a/src/kimchi/API.json
> +++ b/src/kimchi/API.json
> @@ -54,6 +54,12 @@
> "error": "KCHTMPL0026E"
> }
> }
> + },
> + "auto_topology": {
> + "description": "Auto-configure guest CPU topology.",
> + "type": "boolean",
> + "required": false,
> + "error": "KCHTMPL0028E"
> }
> }
> }
> diff --git a/src/kimchi/control/cpuinfo.py b/src/kimchi/control/cpuinfo.py
> new file mode 100644
> index 0000000..3a295ad
> --- /dev/null
> +++ b/src/kimchi/control/cpuinfo.py
> @@ -0,0 +1,37 @@
> +#
> +# Project Kimchi
> +#
> +# Copyright IBM, Corp. 2014
> +#
> +# This library is free software; you can redistribute it and/or
> +# modify it under the terms of the GNU Lesser General Public
> +# License as published by the Free Software Foundation; either
> +# version 2.1 of the License, or (at your option) any later version.
> +#
> +# This library 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 this library; if not, write to the Free Software
> +# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> +
> +from kimchi.control.base import Resource
> +
> +
> +class CPUInfo(Resource):
> + def __init__(self, model):
> + super(CPUInfo, self).__init__(model)
> + self.admin_methods = ['GET']
> + self.uri_fmt = "/host/cpu_info"
> +
> + @property
> + def data(self):
> + return {'arch': self.info['arch'],
> + 'threading_enabled': self.info['guest_threads_enabled'],
> + 'sockets': self.info['sockets'],
> + 'cores_present': self.info['cores_present'],
> + 'cores_online': self.info['cores_available'],
> + 'threads_per_core': self.info['threads_per_core']
> + }
----
All that will not needed.
> diff --git a/src/kimchi/i18n.py b/src/kimchi/i18n.py
> index f789259..7669dbc 100644
> --- a/src/kimchi/i18n.py
> +++ b/src/kimchi/i18n.py
> @@ -146,6 +146,8 @@
> "KCHTMPL0025E": _("When specifying CPU topology, VCPUs must be a product of sockets, cores, and threads."),
> "KCHTMPL0026E": _("When specifying CPU topology, each element must be an integer greater than zero."),
> "KCHTMPL0027E": _("Invalid disk image format. Valid formats: bochs, cloop, cow, dmg, qcow, qcow2, qed, raw, vmdk, vpc."),
> + "KCHTMPL0028E": _("The auto_topology value must be either True or False."),
> + "KCHTMPL0029E": _("This host (or current configuration) does not allow CPU topology."),
>
> "KCHPOOL0001E": _("Storage pool %(name)s already exists"),
> "KCHPOOL0002E": _("Storage pool %(name)s does not exist"),
> diff --git a/src/kimchi/model/cpuinfo.py b/src/kimchi/model/cpuinfo.py
> new file mode 100644
> index 0000000..12f5899
> --- /dev/null
> +++ b/src/kimchi/model/cpuinfo.py
As this file will not needed, you can move the functions needed to
identify the topology to
a new module model/cputopology.py or something like it.
> @@ -0,0 +1,176 @@
> +# modify it under the terms of the GNU Lesser General Public
> +# License as published by the Free Software Foundation; either
> +# version 2.1 of the License, or (at your option) any later version.
> +#
> +# This library 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 this library; if not, write to the Free Software
> +# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> +
> +import platform
> +import libvirt
> +import psutil
> +from xml.etree import ElementTree as ET
> +
> +from kimchi.exception import InvalidParameter
> +from kimchi.utils import kimchi_log, run_command
> +
> +
> +class CPUInfoModel(object):
> + """
> + Get information about a CPU for hyperthreading (on x86)
> + or SMT (on POWER) for logic when creating templates and VMs.
> + """
> +
> + def __init__(self, **kargs):
> + """ Since there are so many similar-seeming variables:
> + - arch = either ppc or x86 (Intel and AMD)
> + - guest_threads_enabled = Can a user specify topology?
> + - sockets = total number of sockets in the system. While nothing
> + uses this value, it's part of topology so we'll track it.
> + - cores_present = total number of cores in the system
> + Note: Cores is often synonymous with CPUs.
> + - cores_available = cores online (in case some were offlined)
> + - cores_per_socket = max cores value for topology
> + - threads_per_core = max threads value for topology
> + """
> + libvirt_topology = None
> + try:
> + connect = libvirt.open(None)
Use LibvirtConnection to establish a connection to libvirt.
One of the args on "kargs" is "conn" which is already an
LibvirtConnection instance.
> + except Exception as e:
> + raise Exception("Unable to get qemu connection: %s" % e.message)
> + try:
> + xml = connect.getCapabilities()
> + capabilities = ET.fromstring(xml)
> + libvirt_topology = capabilities.find('host').find('cpu').\
> + find('topology')
> + if libvirt_topology is None:
> + kimchi_log.info("cpu_info topology not supported.")
> + self.guest_threads_enabled = False
> + self.sockets = 0
> + self.cores_present = 0
> + self.cores_available = 0
> + self.cores_per_socket = 0
> + self.threads_per_core = 0
> + self.max_threads = 0
> + return
> + except Exception as e:
> + raise("Unable to get CPU topology capabilities: %s" % e.message)
> +
> + if platform.machine().startswith('ppc'):
> + # IBM PowerPC
> + self.arch = 'ppc'
> + self.guest_threads_enabled = True
> + out, error, rc = run_command('ppc64_cpu', '--smt')
Only rc!=0 is not enough to check it?
And isn't there a libvirt API to ppc64_cpu?
> + if rc or out is not 'SMT is off':
> + # SMT has to be disabled for guest to use threads as CPUs.
> + self.guest_threads_enabled = False
> + out, error, rc = run_command('ppc64_cpu', '--cores_present')
> + if not rc:
> + self.cores_present = out.split()[-1]
> + out, error, rc = run_command('ppc64_cpu', '--cores_on')
> + if not rc:
> + self.cores_available = out.split()[-1]
> + out, error, rc = run_command('ppc64_cpu', '--threads_per_core')
> + if not rc:
> + self.threads_per_core = out.split()[-1]
> + # This next line doesn't make sense as written, but takes advantage
> + # of the fact that libvirt for ppc reports all the cores on the
> + # system as the cores value in topology (e.g. sockets: 1, cores:
> + # 128, threads: 1)
> + # @TODO: When libvirt on Power starts returning the correct info,
> + # we should be able to remove the seperate logic (or at least put
> + # in a check for the libvirt version, b/c that will break this).
> + self.cores_per_socket = \
> + libvirt.topology.get('cores')/self.threads_per_core
> + # Nothing actually uses 'sockets,' but set it anyway
> + self.sockets = 1
> + else:
> + # Intel or AMD
> + self.arch = 'x86'
> + self.guest_threads_enabled = True
> + self.sockets = int(libvirt_topology.get('sockets'))
> + self.cores_per_socket = int(libvirt_topology.get('cores'))
> + self.cores_present = self.cores_per_socket * self.sockets
> + self.cores_available = psutil.NUM_CPUS
> + self.threads_per_core = int(libvirt_topology.get('threads'))
> +
> + def lookup(self):
> + """
> + The UI can use this data to decide what to display:
> + - SMT (arch = ppc) or HT (arch = x86)
> + - If HT:
> + 1. the UI can look at cores_present and
> + warn the user if he/she creates a VM with more
> + vCPUs than cores (bad performance).
> + 2. The UI could include a suggestion of 'cores_present'
> + or fewer vCPUs next to the CPU box.
> + 3. There could be an actual limit on the number of vCPUs.
> + A user can use this data to decide how to best manually
> + create a VM or template.
> + """
> + return {
> + 'arch': self.arch,
> + 'guest_threads_enabled': self.guest_threads_enabled,
> + 'sockets': self.sockets,
> + 'cores_per_socket': self.cores_per_socket,
> + 'cores_present': self.cores_present,
> + 'cores_availalble': self.cores_available,
> + 'threads_per_core': self.threads_per_core,
> + }
> +
> + def get_rec_topology(self, vcpus, guest=None, smtx=0):
> + """
> + Kimchi will provide a recommended topoology based on the
> + number of virtual CPUs desired and guest OS.
> +
> + param vcpus: should be an integer
> + param guest: should be in the form 'distro:version'
> + param thread_pref: a power of 2, or 0, if no preference (x86).
> + return: topology numbers. If all zero, SMT/hyperthreading not
> + supported.
> + """
> +
> + """
> + Note to remove later ... This will be called from the UI,
> + If Power, smtx should be set.
> +
> + On x86, spreading threads over cores is better than grouping.
> + IOW, for vcpus = 2, sockets = 1, cores = 2, threads = 1 is
> + better than vcpus=2, sockets = 1, cores = 1, threads = 2.
> + """
> +
> + if not self.guest_threads_enabled:
> + return None
> + if vcpus > self.cores_available * self.threads_per_core:
> + # This check should go into template create too?
> + # Or should we allow this?
> + raise InvalidParameter("The number of vcpus is too large \
> + for this system") # @TODO: msgid
> +
> + sockets = 1
> + cores = 1
> + threads = 1
> +
> + if vcpus == 1:
> + return {"sockets": sockets, "cores": cores, "threads": threads}
> +
> + # creating a VM using REST APIs
> + if self.arch is 'ppc' and smtx == 0:
> + smtx = self.threads_per_core
> +
> + if smtx: # Power
> + cores = vcpus/smtx
> + threads = smtx
> +
> + else: # x86
> + # The scheduler will move these around, but we'll split
> + # it up anyway.
> + cores = self.cores_available
> + threads = vcpus/cores
> +
> + return {"sockets": sockets, "cores": cores, "threads": threads}
> diff --git a/src/kimchi/model/host.py b/src/kimchi/model/host.py
> index 8cddcdc..7912311 100644
> --- a/src/kimchi/model/host.py
> +++ b/src/kimchi/model/host.py
> @@ -53,6 +53,7 @@ def __init__(self, **kargs):
> self.task = TaskModel(**kargs)
> self.host_info = self._get_host_info()
>
> + # @TODO: Think about moving this to the new cpuinfo class
> def _get_ppc_cpu_info(self):
> res = {}
> with open('/proc/cpuinfo') as f:
> diff --git a/src/kimchi/model/templates.py b/src/kimchi/model/templates.py
> index ff1070d..e402260 100644
> --- a/src/kimchi/model/templates.py
> +++ b/src/kimchi/model/templates.py
> @@ -25,6 +25,7 @@
> from kimchi.exception import InvalidOperation, InvalidParameter
> from kimchi.exception import NotFoundError, OperationFailed
> from kimchi.kvmusertests import UserTests
> +from kimchi.model.cpuinfo import CPUInfoModel
> from kimchi.utils import pool_name_from_uri
> from kimchi.utils import probe_file_permission_as_user
> from kimchi.vmtemplate import VMTemplate
> @@ -50,18 +51,28 @@ def create(self, params):
>
> cpu_info = params.get('cpu_info')
> if cpu_info:
> + vcpus = params.get('cpus')
> topology = cpu_info.get('topology')
> + auto_topology = cpu_info.get('auto_topology')
> # Check, even though currently only topology
> # is supported.
> if topology:
> sockets = topology['sockets']
> cores = topology['cores']
> threads = topology['threads']
> - vcpus = params.get('cpus')
> if vcpus is None:
> params['cpus'] = sockets * cores * threads
> elif vcpus != sockets * cores * threads:
> raise InvalidParameter("KCHTMPL0025E")
> + elif auto_topology and auto_topology is True:
> + if vcpus is None:
> + vcpus = 1
Why are you assuming it? Isn't this value same of params['cpus'] ?
The default values come from osinfo.py and we should respect them.
> + topology = CPUInfoModel().get_rec_topology(vcpus)
> + if topology:
> + params['cpu_info']['topology'] = topology
> + else:
> + raise InvalidOperation("KCHTMPL0029E")
> +
> else:
> params['cpu_info'] = dict()
>
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