Skip to content

Latest commit

 

History

History
254 lines (185 loc) · 7.25 KB

README.md

File metadata and controls

254 lines (185 loc) · 7.25 KB
Raw

ABOUT

LMIWBEM is a Python library that performs CIM operations using CIM-XML protocol. The library tries to mimic PyWBEM, but does things in different way:

  • TOG-Pegasus client's library is used for communication
  • lazy evaluation of CIM objects is used
  • some minor API was added for performance reasons

Reasons why the library was created:

  • Performance - Using TOG-Pegasus client's library, Boost::Python and C++ STL, CIM operations are executed faster (e.g. ~60% faster Instance enumeration compared to PyWBEM).

    NOTE: performance gain depends on CIM operation; there are CIM operations where the percentage is even higher.

  • Memory - Using PyWBEM, the Python's interpreter can eat up to several GB of memory. In LMIWBEM, C++ allocator for CIM objects is used and unnecessary memory blocks are properly freed and returned to OS. Lazy evaluation (construction) of nested objects helps to perform CIM operations faster and Python does not use additional space for such objects unless it's necessary.

LATEST VERSION

Latest sources of the software can be found at: github repository.

DOCUMENTATION

Extensive documentation be found at documentation.

Full source code examples can be also found at examples.

API documentation is located at API documentation.

INSTALLATION

LMIWBEM has several dependencies:

  • C++ compiler with support of C++98 standard
  • tog-pegasus-libs (2.12.0)
  • boost-python or boost-python3 (1.50.0)
  • python-devel or python3-devel
  • build tools (autoconf, automake, make, ...)

Optional dependencies:

  • openslp-devel
  • openwsman-devel

LMIWBEM supports 2 build systems:

  • Autotools (must precede distutils)
  • Python's distutils.

AUTOTOOLS

To install the module using configure script, follow these steps:

$ ./autogen.sh # if you got sources from git repository
$ mkdir build && cd build
$ ../configure
$ make
# make install

DISTUTILS

To install the module using Python's distutils, follow these steps:

$ ./autogen.sh # if you got sources from git repository
$ mkdir build && cd build
$ ../configure
# python setup.py install

NOTE: It is necessary to run configure script, which generates Python's setup.py for build and installation.

OPTIONS

These options apply for configure and setup.py will be generated based on the options selected:

--with-default-namespace=NAMESPACE; default: root/cimv2
--with-default-trust-store=DIR;     default: /etc/pki/ca-trust/source/anchors/
--with-listener=[yes/no];           default: yes
--with-slp=[yes/no];                default: yes
--with-wsman=[yes/no];              default: no

By default, LMIWBEM is configured to work with Python 2.6.x and 2.7.x. It is possible to build the project with Python 3.x.x compatibility by running configure script with:

--with-python3=yes

If the module is built using distutils, Python version is determined at runtime. Setup with Python 3.x.x:

$ python3 setup.py install

USAGE

Currently supported intrinsic methods:

  • Associators()
  • AssociatorNames()
  • CreateInstance()
  • DeleteInstance()
  • EnumerateClassNames()
  • EnumerateClasses()
  • EnumerateInstanceNames()
  • EnumerateInstances()
  • ExecQuery()
  • GetClass()
  • GetInstance()
  • InvokeMethod()
  • ModifyInstance()
  • References()
  • ReferenceNames()
  • *OpenAssociators()
  • *OpenAssociatorNames()
  • *OpenEnumerateInstances()
  • *OpenEnumerateInstanceNames()
  • *OpenExecQuery()
  • *OpenReferences()
  • *OpenReferenceNames()

*NOTE: WSMAN backend doesn't support pull operations right now.

There is major difference when compared to PyWBEM: using LMIWBEM, it is possible to create and maintain a connection with a CIMOM:

import lmiwbem

conn = lmiwbem.WBEMConnection()
conn.connect('hostname', 'username', 'password')
...
conn.disconnect()

or:

import lmiwbem

conn = lmiwbem.WBEMConnection('https://username:password@hostname:port')
conn.connect()
...
conn.disconnect()

It is possible to create connections in PyWBEM's way:

import lmiwbem

conn = lmiwbem.WBEMConnection('hostname', ('username', 'password'))
...

NOTE: It is not necessary to call .disconnect() when using such structure.

Connection to WSMAN CIMOM:

import lmiwbem

conn = lmiwbem.WBEMConnection('hostname/wsman', ('username', 'password'))
...

NOTE: LMIWBEM needs to be configured to use OpenWSMAN; otherwise CIM-XML backend will be used.

PERFORMANCE

LMI Meta-Command uses "real" world constructions in LMIShell and was used for benchmarking purposes.

SETUP

  • Managed system:

    • openlmi-account-0.4.2-2.fc21
    • openlmi-logicalfile-0.4.2-2.fc21
    • openlmi-hardware-0.4.2-2.fc21
    • openlmi-networking-0.2.2-3.fc21
    • openlmi-service-0.4.2-2.fc21
    • openlmi-storage-0.7.1-2.fc21

  • Client system:

    • openlmi-scripts-account-0.0.1-7.fc20
    • openlmi-scripts-logicalfile-0.0.3-7.fc20
    • openlmi-scripts-hardware-0.0.3-7.fc20
    • openlmi-scripts-networking-0.0.2-7.fc20
    • openlmi-scripts-service-0.1.2-7.fc20
    • openlmi-scripts-storage-0.0.4-7.fc20
    • lmishell with pywbem/lmiwbem

RESULTS

Command PyWBEM LMIWBEM
lmi file list <dir> 21662.043ms (349MB) 6837.136ms (273MB)
lmi group list 411.938ms (241MB) 236.245ms (267MB)
lmi hwinfo 1699.851ms (246MB) 631.720ms (267MB)
lmi net device list 697.675ms (236MB) 348.451ms (267MB)
lmi net device show 3016.917ms (246MB) 1147.636ms (267MB)
lmi net setting list 417.707ms (235MB) 248.474ms (267MB)
lmi service list 60996.685ms (269MB) 58527.529ms (267MB)
lmi storage show /dev/vda 1790.241ms (244MB) 843.254ms (267MB)
lmi storage tree /dev/vda 3069.120ms (246MB) 973.947ms (267MB)
lmi storage fs list 854.803ms (251MB) 487.202ms (267MB)
lmi storage mount list 1503.447ms (248MB) 1063.852ms (267MB)
lmi storage partition list 523.848ms (243MB) 278.820ms (267MB)
lmi storage partition-table list 1861.788ms (246MB) 935.674ms (267MB)
lmi user list 2510.069ms (232MB) 2175.117ms (267MB)

NOTE: LMIWBEM uses Boost::Python, which brings a little overhead with the module itself. This can be seen in memory results.

BUG REPORTS

Report bugs to phatina@redhat.com or lmiwbem issues.