Run ImageStreamTag Imports In Parallel

User Story

As an OpenShift developer
I want ImageStreamImport to import its images in parallel
So that large imagestreams import faster

Acceptance Criteria

• Imageastream tag import performance improves if an imagestream has a high number of tags (ex: > 20)
• First pass - add a hard-coded number of imagestreams tags can be imported in parallel
• Optional - expose the number of import workers as a cluster config.

Launch Checklist

Dependencies identified
Blockers noted and expected delivery timelines set
Design is implementable
Acceptance criteria agreed upon
Story estimated

Notes

Imagestream will only need one update - plan is to add fixed number workers to update the tag.
No API changes expected.
We don't have direct testing of imagestream import - other things indirectly test (ex- build suites which use sample imagestreams)
oc mirror copies images in parallel: https://github.com/openshift/oc/blob/master/pkg/cli/image/mirror/mirror.go

Add pertinent notes here:

• Enhancement proposal link
• Previous product docs
• Best practices
• Known issues

Guiding Questions

User Story

• Is this intended for an administrator, application developer, or other type of OpenShift user?
• What experience level is this intended for? New, experienced, etc.?
• Why is this story important? What problems does this solve? What benefit(s) will the customer experience?
• Is this part of a larger epic or initiative? If so, ensure that the story is linked to the appropriate epic and/or initiative.

Acceptance Criteria

• How should a customer use and/or configure the feature?
• Are there any prerequisites for using/enabling the feature?

Notes

• Is this a new feature, or an enhancement of an existing feature? If the latter, list the feature and docs reference.
• Are there any new terms, abbreviations, or commands introduced with this story? Ex: a new command line argument, a new custom resource.
• Are there any recommended best practices when using this feature?
• On feature completion, are there any known issues that customers should be aware of?