Merge pull request #19366 from ironcladlou/noop-zero-replicas

Support rolling update to 0 desired replicas
This commit is contained in:
Alex Mohr 2016-01-21 15:08:20 -08:00
commit 9546909929
2 changed files with 88 additions and 4 deletions

View File

@ -208,13 +208,20 @@ func (r *RollingUpdater) Update(config *RollingUpdaterConfig) error {
if err != nil {
return err
}
// Further validation.
if maxUnavailable == 0 && maxSurge == 0 {
// Validate maximums.
if desired > 0 && maxUnavailable == 0 && maxSurge == 0 {
return fmt.Errorf("one of maxSurge or maxUnavailable must be specified")
}
// The minumum pods which must remain available througout the update
// calculated for internal convenience.
minAvailable := original - maxUnavailable
minAvailable := int(math.Max(float64(0), float64(desired-maxUnavailable)))
// If the desired new scale is 0, then the max unavailable is necessarily
// the effective scale of the old RC regardless of the configuration
// (equivalent to 100% maxUnavailable).
if desired == 0 {
maxUnavailable = original
minAvailable = 0
}
fmt.Fprintf(out, "Scaling up %s from %d to %d, scaling down %s from %d to 0 (keep %d pods available, don't exceed %d pods)\n",
newRc.Name, newRc.Spec.Replicas, desired, oldRc.Name, oldRc.Spec.Replicas, minAvailable, original+maxSurge)

View File

@ -539,7 +539,7 @@ Scaling foo-v1 down to 0
down{oldReady: 10, newReady: 20, to: 0},
},
output: `Created foo-v2
Scaling up foo-v2 from 0 to 20, scaling down foo-v1 from 10 to 0 (keep 10 pods available, don't exceed 70 pods)
Scaling up foo-v2 from 0 to 20, scaling down foo-v1 from 10 to 0 (keep 20 pods available, don't exceed 70 pods)
Scaling foo-v2 up to 20
Scaling foo-v1 down to 0
`,
@ -557,6 +557,83 @@ Scaling foo-v1 down to 0
output: `Continuing update with existing controller foo-v2.
Scaling up foo-v2 from 1 to 1, scaling down foo-v1 from 1 to 0 (keep 1 pods available, don't exceed 2 pods)
Scaling foo-v1 down to 0
`,
},
{
name: "3->0 1/1 desired 0 (absolute values)",
oldRc: oldRc(3, 3),
newRc: newRc(0, 0),
newRcExists: true,
maxUnavail: intstr.FromInt(1),
maxSurge: intstr.FromInt(1),
expected: []interface{}{
down{oldReady: 3, newReady: 0, to: 0},
},
output: `Continuing update with existing controller foo-v2.
Scaling up foo-v2 from 0 to 0, scaling down foo-v1 from 3 to 0 (keep 0 pods available, don't exceed 4 pods)
Scaling foo-v1 down to 0
`,
},
{
name: "3->0 10/10 desired 0 (percentages)",
oldRc: oldRc(3, 3),
newRc: newRc(0, 0),
newRcExists: true,
maxUnavail: intstr.FromString("10%"),
maxSurge: intstr.FromString("10%"),
expected: []interface{}{
down{oldReady: 3, newReady: 0, to: 0},
},
output: `Continuing update with existing controller foo-v2.
Scaling up foo-v2 from 0 to 0, scaling down foo-v1 from 3 to 0 (keep 0 pods available, don't exceed 3 pods)
Scaling foo-v1 down to 0
`,
},
{
name: "3->0 10/10 desired 0 (create new RC)",
oldRc: oldRc(3, 3),
newRc: newRc(0, 0),
newRcExists: false,
maxUnavail: intstr.FromString("10%"),
maxSurge: intstr.FromString("10%"),
expected: []interface{}{
down{oldReady: 3, newReady: 0, to: 0},
},
output: `Created foo-v2
Scaling up foo-v2 from 0 to 0, scaling down foo-v1 from 3 to 0 (keep 0 pods available, don't exceed 3 pods)
Scaling foo-v1 down to 0
`,
},
{
name: "0->0 1/1 desired 0 (absolute values)",
oldRc: oldRc(0, 0),
newRc: newRc(0, 0),
newRcExists: true,
maxUnavail: intstr.FromInt(1),
maxSurge: intstr.FromInt(1),
expected: []interface{}{
down{oldReady: 0, newReady: 0, to: 0},
},
output: `Continuing update with existing controller foo-v2.
Scaling up foo-v2 from 0 to 0, scaling down foo-v1 from 0 to 0 (keep 0 pods available, don't exceed 1 pods)
`,
}, {
name: "30->2 50%/0",
oldRc: oldRc(30, 30),
newRc: newRc(0, 2),
newRcExists: false,
maxUnavail: intstr.FromString("50%"),
maxSurge: intstr.FromInt(0),
expected: []interface{}{
down{oldReady: 30, newReady: 0, to: 1},
up{2},
down{oldReady: 1, newReady: 2, to: 0},
},
output: `Created foo-v2
Scaling up foo-v2 from 0 to 2, scaling down foo-v1 from 30 to 0 (keep 1 pods available, don't exceed 30 pods)
Scaling foo-v1 down to 1
Scaling foo-v2 up to 2
Scaling foo-v1 down to 0
`,
},
}