Add support for pipelines controller statefulset ordinals #2361
Conversation
tekton-robot
added
release-note
tekton-robot
added
the
size/L
jkhelil
force-pushed
the
statefulset_ordinals
branch
8 times, most recently
from
cb48950
to
ca0d5eb
Compare
jkhelil
changed the title
tekton-robot
removed
the
do-not-merge/work-in-progress
jkhelil
force-pushed
the
statefulset_ordinals
branch
10 times, most recently
from
a9a023a
to
f704975
Compare
|
The following is the coverage report on the affected files.
|
jkhelil
force-pushed
the
statefulset_ordinals
branch
from
f704975
to
28b6ca2
Compare
| if p.Performance.StatefulsetOrdinals == nil { | ||
| p.Performance.StatefulsetOrdinals = ptr.Bool(false) | ||
| } else if *p.Performance.StatefulsetOrdinals { | ||
| if p.Performance.Replicas != nil && *p.Performance.Replicas > 1 { |
There was a problem hiding this comment.
If p.Performance.Replicas != nil then we might have to set the buckets to 1
There was a problem hiding this comment.
in statefulset mode, bucket should be equal to replicas, not to 1
There was a problem hiding this comment.
@jkhelil I guess @PuneetPunamiya try to say bucket should be 1, when p.Performance.Replicas == nil
There was a problem hiding this comment.
yeah sorry for the confusion
+1 on what @jkandasa said
There was a problem hiding this comment.
When replicas is not specified (it's nil), the default behavior of a StatefulSet is to create a single pod, in StatefulSet's Knative mode, the default behavior is to create one bucket, so there is no need to enforce that mode, it works by default.
However, when replicas is explicitly set (not nil), I found that if we don’t enforce the bucket assignment to equal to replicas, the election mode and StatefulSet mode can interfere with each other. This results in some pods being in election mode while others are in StatefulSet mode, leading to inconsistent behavior.
|
[APPROVALNOTIFIER] This PR is APPROVED This pull-request has been approved by: jkandasa The full list of commands accepted by this bot can be found here. The pull request process is described here
Needs approval from an approver in each of these files:
Approvers can indicate their approval by writing |
tekton-robot
added
the
approved
jkhelil
force-pushed
the
statefulset_ordinals
branch
from
6e12802
to
41c04dc
Compare
|
The following is the coverage report on the affected files.
|
jkhelil
force-pushed
the
statefulset_ordinals
branch
from
41c04dc
to
6875fc5
Compare
|
The following is the coverage report on the affected files.
|
jkhelil
force-pushed
the
statefulset_ordinals
branch
from
6875fc5
to
6c9ca21
Compare
|
The following is the coverage report on the affected files.
|
|
@PuneetPunamiya PTAL |
|
Thanks @jkhelil 🤙🏻 |
Changes
To handle HA on pipelines controller, there are two mechanisms available for scaling controllers horizontally via knative/pkg:
- Using leader election, which allows for failover, but can result in hot-spotting.(this is the default pipelines controller mode)
- Using StatefulSet ordinals, which doesn't allow for failover, but guarantees keys are evenly spread across replicas.
This PR adds support for pipelines controller statefulset ordinals
Submitter Checklist
These are the criteria that every PR should meet, please check them off as you
review them:
make test lintbefore submitting a PRSee the contribution guide for more details.
Release Notes