797d101a64
According to my diagnosis [1], currently v2 API client consumed a lot of CPU times by JSON schema validation on image model initialization stage for image listing case. Because each image entry will triggers one validation operation which spent most CPU clocks. (My test env has 1002 image entries now, so it's O(N) logic obviously). This fix changed the original logic, it doesn't validate each image entry but do it only on first image entry for each page. This approach is a trade-off, it balanced the data validity and performance. As comparison [3], under the fixed new logic, the execution time of image listing is about four times as fast as old logic. [1] Clock type: CPU Ordered by: totaltime, desc name ncall ttot ..nt/v2/images.py:34 Controller.list 1003 12.08480 ../warlock/core.py:30 image.__init__ 1002 11.91074 ..warlock/model.py:28 image.__init__ 1002 11.90463 ..arlock/model.py:130 image.validate 1002 11.73838 ..nschema/validators.py:388 validate 1002 11.73682 [2] name ncall ttot ..nt/v2/images.py:35 Controller.list 1003 1.100710 ..nceclient/v2/images.py:45 paginate 256.. 1.099965 ../warlock/core.py:30 image.__init__ 1002 0.944762 ..warlock/model.py:28 image.__init__ 1002 0.939725 ..arlock/model.py:130 image.validate 51 0.779653 ..nschema/validators.py:388 validate 51 0.779431 [3] $ time glance --os-image-api-version 2 image-list | grep 'test-' | wc -l 1000 real 0m16.606s user 0m10.629s sys 0m2.540s $ time glance --os-image-api-version 2 image-list | grep 'test-' | wc -l 1000 real 0m4.151s user 0m1.080s sys 0m0.092s Change-Id: Ia6598d3c06a5ff516277053c2b6fa5db744fe9cf Signed-off-by: Zhi Yan Liu <zhiyanl@cn.ibm.com>
Python bindings to the OpenStack Images API
This is a client library for Glance built on the OpenStack Images
API. It provides a Python API (the glanceclient module) and
a command-line tool (glance). This library fully supports
the v1 Images API, while support for the v2 API is in progress.
Development takes place via the usual OpenStack processes as outlined in the OpenStack wiki. The master repository is on GitHub.
See release notes and more at http://docs.openstack.org/developer/python-glanceclient/.