openstack/glance-specs
Code Issues Proposed changes

Revert "Add support of cinder's new attachment API"

Browse Source 
This reverts commit 8503faee7c91ffc21440a7bf170cc404999308e5.

Reason for revert: Reverting the change as noticed lately that the spec file is not .rst so it does not caught the syntax errors also it is missing the entry in the spec/xena/index.rst so the actually merged spec is not displayed/listed in the final output [0]

[0] https://5987422f5decdefb3e3d-3f28c2c0c6b192e8ac5a4ae954bec2d0.ssl.cf5.rackcdn.com/787515/1/gate/openstack-tox-docs/ea34475/docs/specs/xena/approved/index.html

Change-Id: I966e2a5426195300839315cb7635d0fe925b50a9
This commit is contained in:
Abhishek Kekane 2021-06-02 16:58:32 +00:00
parent 8503faee7c
commit 7499c85bf1
1 changed files with 0 additions and 142 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

142
specs/xena/approved/glance_store/attachment-api-and-multiattach-support
View File

@ -1,142 +0,0 @@
..
This work is licensed under a Creative Commons Attribution 3.0 Unported
License.
http://creativecommons.org/licenses/by/3.0/legalcode
=======================================================
Add new cinder's attachment API and multiattach support
=======================================================
https://blueprints.launchpad.net/glance-store/+spec/attachment-api-and-multiattach-support
Make glance cinder store use cinder's new attachment APIs for image operations.
Problem description
===================
Currently when we make simultaneous requests to glance for using the image to
create multiple volumes or launch multiple instances, the same image volume needs
to be attached multiple times to serve the requests and since the support doesn't
exist in glance cinder store, some of the requests fails.
Proposed change
===============
Cinder's new attachment API was introduced in microversion 3.27 which should be
supported by cinder and is required to pass while making calls through cinderclient.
There were 2 new methods introduced, attachment_complete in MV 3.44 and passing
attach mode during attachment_create in MV 3.54 which are also required and hence
we will be using MV 3.54 for attachment related operations.
All these changes are required prior to adding the multiattach handling.
This should be a 2 stage change:
1) Replace existing API calls to cinder for attachment with new attachment API
calls
2) Add multiattach handling for glance cinder usecase
Alternatives
------------
Use cinder's image volume cache that will clone the first bootable volume created
from image and subsequent requests will result in cinder's clone operation instead
of downloading the image from glance.
Data model impact
-----------------
None
REST API impact
---------------
None
Security impact
---------------
None
Notifications impact
--------------------
None
Other end user impact
---------------------
None
Performance Impact
------------------
The current number of calls to cinder will be reduced resulting in performance
improvement. Example: initialize_connection and attach calls will be replaced
by attachment_update and similarly terminate_connection and detach calls will
be replaced by attachment_delete.
Other deployer impact
---------------------
None
Developer impact
----------------
None
Implementation
==============
Assignee(s)
-----------
Primary assignee:
* whoami-rajat
Other contributors:
None
Reviewers
---------
Core reviewer(s):
* abhishek-kekane
* jokke
* rosmaita
* smcginnis
Work Items
----------
* Replace existing calls to old attachment methods with the new attachment API
calls
* Modify cinderclient calls to include microversion
* Add code for multiattach handling
* Add appropriate unit tests
Dependencies
============
None
Testing
=======
Unit tests to have the code coverage and the new attachment code path will
be tested with the glance cinder tempest job running on glance gate.
Documentation Impact
====================
None
References
==========
None