forked from hashicorp/nomad
/
reconcile.go
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/
reconcile.go
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package scheduler
import (
"fmt"
"time"
"sort"
log "github.com/hashicorp/go-hclog"
"github.com/hashicorp/nomad/helper"
"github.com/hashicorp/nomad/helper/uuid"
"github.com/hashicorp/nomad/nomad/structs"
)
const (
// batchedFailedAllocWindowSize is the window size used
// to batch up failed allocations before creating an eval
batchedFailedAllocWindowSize = 5 * time.Second
// rescheduleWindowSize is the window size relative to
// current time within which reschedulable allocations are placed.
// This helps protect against small clock drifts between servers
rescheduleWindowSize = 1 * time.Second
)
// allocUpdateType takes an existing allocation and a new job definition and
// returns whether the allocation can ignore the change, requires a destructive
// update, or can be inplace updated. If it can be inplace updated, an updated
// allocation that has the new resources and alloc metrics attached will be
// returned.
type allocUpdateType func(existing *structs.Allocation, newJob *structs.Job,
newTG *structs.TaskGroup) (ignore, destructive bool, updated *structs.Allocation)
// allocReconciler is used to determine the set of allocations that require
// placement, inplace updating or stopping given the job specification and
// existing cluster state. The reconciler should only be used for batch and
// service jobs.
type allocReconciler struct {
// logger is used to log debug information. Logging should be kept at a
// minimal here
logger log.Logger
// canInplace is used to check if the allocation can be inplace upgraded
allocUpdateFn allocUpdateType
// batch marks whether the job is a batch job
batch bool
// job is the job being operated on, it may be nil if the job is being
// stopped via a purge
job *structs.Job
// jobID is the ID of the job being operated on. The job may be nil if it is
// being stopped so we require this separately.
jobID string
// oldDeployment is the last deployment for the job
oldDeployment *structs.Deployment
// deployment is the current deployment for the job
deployment *structs.Deployment
// deploymentPaused marks whether the deployment is paused
deploymentPaused bool
// deploymentFailed marks whether the deployment is failed
deploymentFailed bool
// taintedNodes contains a map of nodes that are tainted
taintedNodes map[string]*structs.Node
// existingAllocs is non-terminal existing allocations
existingAllocs []*structs.Allocation
// evalID is the ID of the evaluation that triggered the reconciler
evalID string
// now is the time used when determining rescheduling eligibility
// defaults to time.Now, and overidden in unit tests
now time.Time
// result is the results of the reconcile. During computation it can be
// used to store intermediate state
result *reconcileResults
}
// reconcileResults contains the results of the reconciliation and should be
// applied by the scheduler.
type reconcileResults struct {
// deployment is the deployment that should be created or updated as a
// result of scheduling
deployment *structs.Deployment
// deploymentUpdates contains a set of deployment updates that should be
// applied as a result of scheduling
deploymentUpdates []*structs.DeploymentStatusUpdate
// place is the set of allocations to place by the scheduler
place []allocPlaceResult
// destructiveUpdate is the set of allocations to apply a destructive update to
destructiveUpdate []allocDestructiveResult
// inplaceUpdate is the set of allocations to apply an inplace update to
inplaceUpdate []*structs.Allocation
// stop is the set of allocations to stop
stop []allocStopResult
// attributeUpdates are updates to the allocation that are not from a
// jobspec change.
attributeUpdates map[string]*structs.Allocation
// desiredTGUpdates captures the desired set of changes to make for each
// task group.
desiredTGUpdates map[string]*structs.DesiredUpdates
// desiredFollowupEvals is the map of follow up evaluations to create per task group
// This is used to create a delayed evaluation for rescheduling failed allocations.
desiredFollowupEvals map[string][]*structs.Evaluation
}
// delayedRescheduleInfo contains the allocation id and a time when its eligible to be rescheduled.
// this is used to create follow up evaluations
type delayedRescheduleInfo struct {
// allocID is the ID of the allocation eligible to be rescheduled
allocID string
alloc *structs.Allocation
// rescheduleTime is the time to use in the delayed evaluation
rescheduleTime time.Time
}
func (r *reconcileResults) GoString() string {
base := fmt.Sprintf("Total changes: (place %d) (destructive %d) (inplace %d) (stop %d)",
len(r.place), len(r.destructiveUpdate), len(r.inplaceUpdate), len(r.stop))
if r.deployment != nil {
base += fmt.Sprintf("\nCreated Deployment: %q", r.deployment.ID)
}
for _, u := range r.deploymentUpdates {
base += fmt.Sprintf("\nDeployment Update for ID %q: Status %q; Description %q",
u.DeploymentID, u.Status, u.StatusDescription)
}
for tg, u := range r.desiredTGUpdates {
base += fmt.Sprintf("\nDesired Changes for %q: %#v", tg, u)
}
return base
}
// Changes returns the number of total changes
func (r *reconcileResults) Changes() int {
return len(r.place) + len(r.inplaceUpdate) + len(r.stop)
}
// NewAllocReconciler creates a new reconciler that should be used to determine
// the changes required to bring the cluster state inline with the declared jobspec
func NewAllocReconciler(logger log.Logger, allocUpdateFn allocUpdateType, batch bool,
jobID string, job *structs.Job, deployment *structs.Deployment,
existingAllocs []*structs.Allocation, taintedNodes map[string]*structs.Node, evalID string) *allocReconciler {
return &allocReconciler{
logger: logger.Named("reconciler"),
allocUpdateFn: allocUpdateFn,
batch: batch,
jobID: jobID,
job: job,
deployment: deployment.Copy(),
existingAllocs: existingAllocs,
taintedNodes: taintedNodes,
evalID: evalID,
now: time.Now(),
result: &reconcileResults{
desiredTGUpdates: make(map[string]*structs.DesiredUpdates),
desiredFollowupEvals: make(map[string][]*structs.Evaluation),
},
}
}
// Compute reconciles the existing cluster state and returns the set of changes
// required to converge the job spec and state
func (a *allocReconciler) Compute() *reconcileResults {
// Create the allocation matrix
m := newAllocMatrix(a.job, a.existingAllocs)
// Handle stopping unneeded deployments
a.cancelDeployments()
// If we are just stopping a job we do not need to do anything more than
// stopping all running allocs
if a.job.Stopped() {
a.handleStop(m)
return a.result
}
// Detect if the deployment is paused
if a.deployment != nil {
a.deploymentPaused = a.deployment.Status == structs.DeploymentStatusPaused
a.deploymentFailed = a.deployment.Status == structs.DeploymentStatusFailed
}
// Reconcile each group
complete := true
for group, as := range m {
groupComplete := a.computeGroup(group, as)
complete = complete && groupComplete
}
// Mark the deployment as complete if possible
if a.deployment != nil && complete {
a.result.deploymentUpdates = append(a.result.deploymentUpdates, &structs.DeploymentStatusUpdate{
DeploymentID: a.deployment.ID,
Status: structs.DeploymentStatusSuccessful,
StatusDescription: structs.DeploymentStatusDescriptionSuccessful,
})
}
// Set the description of a created deployment
if d := a.result.deployment; d != nil {
if d.RequiresPromotion() {
if d.HasAutoPromote() {
d.StatusDescription = structs.DeploymentStatusDescriptionRunningAutoPromotion
} else {
d.StatusDescription = structs.DeploymentStatusDescriptionRunningNeedsPromotion
}
}
}
return a.result
}
// cancelDeployments cancels any deployment that is not needed
func (a *allocReconciler) cancelDeployments() {
// If the job is stopped and there is a non-terminal deployment, cancel it
if a.job.Stopped() {
if a.deployment != nil && a.deployment.Active() {
a.result.deploymentUpdates = append(a.result.deploymentUpdates, &structs.DeploymentStatusUpdate{
DeploymentID: a.deployment.ID,
Status: structs.DeploymentStatusCancelled,
StatusDescription: structs.DeploymentStatusDescriptionStoppedJob,
})
}
// Nothing else to do
a.oldDeployment = a.deployment
a.deployment = nil
return
}
d := a.deployment
if d == nil {
return
}
// Check if the deployment is active and referencing an older job and cancel it
if d.JobCreateIndex != a.job.CreateIndex || d.JobVersion != a.job.Version {
if d.Active() {
a.result.deploymentUpdates = append(a.result.deploymentUpdates, &structs.DeploymentStatusUpdate{
DeploymentID: a.deployment.ID,
Status: structs.DeploymentStatusCancelled,
StatusDescription: structs.DeploymentStatusDescriptionNewerJob,
})
}
a.oldDeployment = d
a.deployment = nil
}
// Clear it as the current deployment if it is successful
if d.Status == structs.DeploymentStatusSuccessful {
a.oldDeployment = d
a.deployment = nil
}
}
// handleStop marks all allocations to be stopped, handling the lost case
func (a *allocReconciler) handleStop(m allocMatrix) {
for group, as := range m {
as = filterByTerminal(as)
untainted, migrate, lost := as.filterByTainted(a.taintedNodes)
a.markStop(untainted, "", allocNotNeeded)
a.markStop(migrate, "", allocNotNeeded)
a.markStop(lost, structs.AllocClientStatusLost, allocLost)
desiredChanges := new(structs.DesiredUpdates)
desiredChanges.Stop = uint64(len(as))
a.result.desiredTGUpdates[group] = desiredChanges
}
}
// markStop is a helper for marking a set of allocation for stop with a
// particular client status and description.
func (a *allocReconciler) markStop(allocs allocSet, clientStatus, statusDescription string) {
for _, alloc := range allocs {
a.result.stop = append(a.result.stop, allocStopResult{
alloc: alloc,
clientStatus: clientStatus,
statusDescription: statusDescription,
})
}
}
// computeGroup reconciles state for a particular task group. It returns whether
// the deployment it is for is complete with regards to the task group.
func (a *allocReconciler) computeGroup(group string, all allocSet) bool {
// Create the desired update object for the group
desiredChanges := new(structs.DesiredUpdates)
a.result.desiredTGUpdates[group] = desiredChanges
// Get the task group. The task group may be nil if the job was updates such
// that the task group no longer exists
tg := a.job.LookupTaskGroup(group)
// If the task group is nil, then the task group has been removed so all we
// need to do is stop everything
if tg == nil {
untainted, migrate, lost := all.filterByTainted(a.taintedNodes)
a.markStop(untainted, "", allocNotNeeded)
a.markStop(migrate, "", allocNotNeeded)
a.markStop(lost, structs.AllocClientStatusLost, allocLost)
desiredChanges.Stop = uint64(len(untainted) + len(migrate) + len(lost))
return true
}
// Get the deployment state for the group
var dstate *structs.DeploymentState
existingDeployment := false
if a.deployment != nil {
dstate, existingDeployment = a.deployment.TaskGroups[group]
}
if !existingDeployment {
dstate = &structs.DeploymentState{}
if !tg.Update.IsEmpty() {
dstate.AutoRevert = tg.Update.AutoRevert
dstate.AutoPromote = tg.Update.AutoPromote
dstate.ProgressDeadline = tg.Update.ProgressDeadline
}
}
// Filter allocations that do not need to be considered because they are
// from an older job version and are terminal.
all, ignore := a.filterOldTerminalAllocs(all)
desiredChanges.Ignore += uint64(len(ignore))
// canaries is the set of canaries for the current deployment and all is all
// allocs including the canaries
canaries, all := a.handleGroupCanaries(all, desiredChanges)
// Determine what set of allocations are on tainted nodes
untainted, migrate, lost := all.filterByTainted(a.taintedNodes)
// Determine what set of terminal allocations need to be rescheduled
untainted, rescheduleNow, rescheduleLater := untainted.filterByRescheduleable(a.batch, a.now, a.evalID, a.deployment)
// Create batched follow up evaluations for allocations that are
// reschedulable later and mark the allocations for in place updating
a.handleDelayedReschedules(rescheduleLater, all, tg.Name)
// Create a structure for choosing names. Seed with the taken names which is
// the union of untainted and migrating nodes (includes canaries)
nameIndex := newAllocNameIndex(a.jobID, group, tg.Count, untainted.union(migrate, rescheduleNow))
// Stop any unneeded allocations and update the untainted set to not
// included stopped allocations.
canaryState := dstate != nil && dstate.DesiredCanaries != 0 && !dstate.Promoted
stop := a.computeStop(tg, nameIndex, untainted, migrate, lost, canaries, canaryState)
desiredChanges.Stop += uint64(len(stop))
untainted = untainted.difference(stop)
// Do inplace upgrades where possible and capture the set of upgrades that
// need to be done destructively.
ignore, inplace, destructive := a.computeUpdates(tg, untainted)
desiredChanges.Ignore += uint64(len(ignore))
desiredChanges.InPlaceUpdate += uint64(len(inplace))
if !existingDeployment {
dstate.DesiredTotal += len(destructive) + len(inplace)
}
// Remove the canaries now that we have handled rescheduling so that we do
// not consider them when making placement decisions.
if canaryState {
untainted = untainted.difference(canaries)
}
// The fact that we have destructive updates and have less canaries than is
// desired means we need to create canaries
numDestructive := len(destructive)
strategy := tg.Update
canariesPromoted := dstate != nil && dstate.Promoted
requireCanary := numDestructive != 0 && strategy != nil && len(canaries) < strategy.Canary && !canariesPromoted
if requireCanary && !a.deploymentPaused && !a.deploymentFailed {
number := strategy.Canary - len(canaries)
desiredChanges.Canary += uint64(number)
if !existingDeployment {
dstate.DesiredCanaries = strategy.Canary
}
for _, name := range nameIndex.NextCanaries(uint(number), canaries, destructive) {
a.result.place = append(a.result.place, allocPlaceResult{
name: name,
canary: true,
taskGroup: tg,
})
}
}
// Determine how many we can place
canaryState = dstate != nil && dstate.DesiredCanaries != 0 && !dstate.Promoted
limit := a.computeLimit(tg, untainted, destructive, migrate, canaryState)
// Place if:
// * The deployment is not paused or failed
// * Not placing any canaries
// * If there are any canaries that they have been promoted
place := a.computePlacements(tg, nameIndex, untainted, migrate, rescheduleNow)
if !existingDeployment {
dstate.DesiredTotal += len(place)
}
// deploymentPlaceReady tracks whether the deployment is in a state where
// placements can be made without any other consideration.
deploymentPlaceReady := !a.deploymentPaused && !a.deploymentFailed && !canaryState
if deploymentPlaceReady {
desiredChanges.Place += uint64(len(place))
for _, p := range place {
a.result.place = append(a.result.place, p)
}
a.markStop(rescheduleNow, "", allocRescheduled)
desiredChanges.Stop += uint64(len(rescheduleNow))
min := helper.IntMin(len(place), limit)
limit -= min
} else if !deploymentPlaceReady {
// We do not want to place additional allocations but in the case we
// have lost allocations or allocations that require rescheduling now,
// we do so regardless to avoid odd user experiences.
if len(lost) != 0 {
allowed := helper.IntMin(len(lost), len(place))
desiredChanges.Place += uint64(allowed)
for _, p := range place[:allowed] {
a.result.place = append(a.result.place, p)
}
}
// Handle rescheduling of failed allocations even if the deployment is
// failed. We do not reschedule if the allocation is part of the failed
// deployment.
if now := len(rescheduleNow); now != 0 {
for _, p := range place {
prev := p.PreviousAllocation()
if p.IsRescheduling() && !(a.deploymentFailed && prev != nil && a.deployment.ID == prev.DeploymentID) {
a.result.place = append(a.result.place, p)
desiredChanges.Place++
a.result.stop = append(a.result.stop, allocStopResult{
alloc: prev,
statusDescription: allocRescheduled,
})
desiredChanges.Stop++
}
}
}
}
if deploymentPlaceReady {
// Do all destructive updates
min := helper.IntMin(len(destructive), limit)
desiredChanges.DestructiveUpdate += uint64(min)
desiredChanges.Ignore += uint64(len(destructive) - min)
for _, alloc := range destructive.nameOrder()[:min] {
a.result.destructiveUpdate = append(a.result.destructiveUpdate, allocDestructiveResult{
placeName: alloc.Name,
placeTaskGroup: tg,
stopAlloc: alloc,
stopStatusDescription: allocUpdating,
})
}
} else {
desiredChanges.Ignore += uint64(len(destructive))
}
// Migrate all the allocations
desiredChanges.Migrate += uint64(len(migrate))
for _, alloc := range migrate.nameOrder() {
a.result.stop = append(a.result.stop, allocStopResult{
alloc: alloc,
statusDescription: allocMigrating,
})
a.result.place = append(a.result.place, allocPlaceResult{
name: alloc.Name,
canary: false,
taskGroup: tg,
previousAlloc: alloc,
})
}
// Create new deployment if:
// 1. Updating a job specification
// 2. No running allocations (first time running a job)
updatingSpec := len(destructive) != 0 || len(a.result.inplaceUpdate) != 0
hadRunning := false
for _, alloc := range all {
if alloc.Job.Version == a.job.Version && alloc.Job.CreateIndex == a.job.CreateIndex {
hadRunning = true
break
}
}
// Create a new deployment if necessary
if !existingDeployment && !strategy.IsEmpty() && dstate.DesiredTotal != 0 && (!hadRunning || updatingSpec) {
// A previous group may have made the deployment already
if a.deployment == nil {
a.deployment = structs.NewDeployment(a.job)
a.result.deployment = a.deployment
}
// Attach the groups deployment state to the deployment
a.deployment.TaskGroups[group] = dstate
}
// deploymentComplete is whether the deployment is complete which largely
// means that no placements were made or desired to be made
deploymentComplete := len(destructive)+len(inplace)+len(place)+len(migrate)+len(rescheduleNow)+len(rescheduleLater) == 0 && !requireCanary
// Final check to see if the deployment is complete is to ensure everything
// is healthy
if deploymentComplete && a.deployment != nil {
if dstate, ok := a.deployment.TaskGroups[group]; ok {
if dstate.HealthyAllocs < helper.IntMax(dstate.DesiredTotal, dstate.DesiredCanaries) || // Make sure we have enough healthy allocs
(dstate.DesiredCanaries > 0 && !dstate.Promoted) { // Make sure we are promoted if we have canaries
deploymentComplete = false
}
}
}
return deploymentComplete
}
// filterOldTerminalAllocs filters allocations that should be ignored since they
// are allocations that are terminal from a previous job version.
func (a *allocReconciler) filterOldTerminalAllocs(all allocSet) (filtered, ignore allocSet) {
if !a.batch {
return all, nil
}
filtered = filtered.union(all)
ignored := make(map[string]*structs.Allocation)
// Ignore terminal batch jobs from older versions
for id, alloc := range filtered {
older := alloc.Job.Version < a.job.Version || alloc.Job.CreateIndex < a.job.CreateIndex
if older && alloc.TerminalStatus() {
delete(filtered, id)
ignored[id] = alloc
}
}
return filtered, ignored
}
// handleGroupCanaries handles the canaries for the group by stopping the
// unneeded ones and returning the current set of canaries and the updated total
// set of allocs for the group
func (a *allocReconciler) handleGroupCanaries(all allocSet, desiredChanges *structs.DesiredUpdates) (canaries, newAll allocSet) {
// Stop any canary from an older deployment or from a failed one
var stop []string
// Cancel any non-promoted canaries from the older deployment
if a.oldDeployment != nil {
for _, s := range a.oldDeployment.TaskGroups {
if !s.Promoted {
stop = append(stop, s.PlacedCanaries...)
}
}
}
// Cancel any non-promoted canaries from a failed deployment
if a.deployment != nil && a.deployment.Status == structs.DeploymentStatusFailed {
for _, s := range a.deployment.TaskGroups {
if !s.Promoted {
stop = append(stop, s.PlacedCanaries...)
}
}
}
// stopSet is the allocSet that contains the canaries we desire to stop from
// above.
stopSet := all.fromKeys(stop)
a.markStop(stopSet, "", allocNotNeeded)
desiredChanges.Stop += uint64(len(stopSet))
all = all.difference(stopSet)
// Capture our current set of canaries and handle any migrations that are
// needed by just stopping them.
if a.deployment != nil {
var canaryIDs []string
for _, s := range a.deployment.TaskGroups {
canaryIDs = append(canaryIDs, s.PlacedCanaries...)
}
canaries = all.fromKeys(canaryIDs)
untainted, migrate, lost := canaries.filterByTainted(a.taintedNodes)
a.markStop(migrate, "", allocMigrating)
a.markStop(lost, structs.AllocClientStatusLost, allocLost)
canaries = untainted
all = all.difference(migrate, lost)
}
return canaries, all
}
// computeLimit returns the placement limit for a particular group. The inputs
// are the group definition, the untainted, destructive, and migrate allocation
// set and whether we are in a canary state.
func (a *allocReconciler) computeLimit(group *structs.TaskGroup, untainted, destructive, migrate allocSet, canaryState bool) int {
// If there is no update strategy or deployment for the group we can deploy
// as many as the group has
if group.Update.IsEmpty() || len(destructive)+len(migrate) == 0 {
return group.Count
} else if a.deploymentPaused || a.deploymentFailed {
// If the deployment is paused or failed, do not create anything else
return 0
}
// If we have canaries and they have not been promoted the limit is 0
if canaryState {
return 0
}
// If we have been promoted or there are no canaries, the limit is the
// configured MaxParallel minus any outstanding non-healthy alloc for the
// deployment
limit := group.Update.MaxParallel
if a.deployment != nil {
partOf, _ := untainted.filterByDeployment(a.deployment.ID)
for _, alloc := range partOf {
// An unhealthy allocation means nothing else should be happen.
if alloc.DeploymentStatus.IsUnhealthy() {
return 0
}
if !alloc.DeploymentStatus.IsHealthy() {
limit--
}
}
}
// The limit can be less than zero in the case that the job was changed such
// that it required destructive changes and the count was scaled up.
if limit < 0 {
return 0
}
return limit
}
// computePlacement returns the set of allocations to place given the group
// definition, the set of untainted, migrating and reschedule allocations for the group.
func (a *allocReconciler) computePlacements(group *structs.TaskGroup,
nameIndex *allocNameIndex, untainted, migrate allocSet, reschedule allocSet) []allocPlaceResult {
// Add rescheduled placement results
var place []allocPlaceResult
for _, alloc := range reschedule {
place = append(place, allocPlaceResult{
name: alloc.Name,
taskGroup: group,
previousAlloc: alloc,
reschedule: true,
canary: alloc.DeploymentStatus.IsCanary(),
})
}
// Hot path the nothing to do case
existing := len(untainted) + len(migrate) + len(reschedule)
if existing >= group.Count {
return place
}
// Add remaining placement results
if existing < group.Count {
for _, name := range nameIndex.Next(uint(group.Count - existing)) {
place = append(place, allocPlaceResult{
name: name,
taskGroup: group,
})
}
}
return place
}
// computeStop returns the set of allocations that are marked for stopping given
// the group definition, the set of allocations in various states and whether we
// are canarying.
func (a *allocReconciler) computeStop(group *structs.TaskGroup, nameIndex *allocNameIndex,
untainted, migrate, lost, canaries allocSet, canaryState bool) allocSet {
// Mark all lost allocations for stop. Previous allocation doesn't matter
// here since it is on a lost node
var stop allocSet
stop = stop.union(lost)
a.markStop(lost, structs.AllocClientStatusLost, allocLost)
// If we are still deploying or creating canaries, don't stop them
if canaryState {
untainted = untainted.difference(canaries)
}
// Hot path the nothing to do case
remove := len(untainted) + len(migrate) - group.Count
if remove <= 0 {
return stop
}
// Filter out any terminal allocations from the untainted set
// This is so that we don't try to mark them as stopped redundantly
untainted = filterByTerminal(untainted)
// Prefer stopping any alloc that has the same name as the canaries if we
// are promoted
if !canaryState && len(canaries) != 0 {
canaryNames := canaries.nameSet()
for id, alloc := range untainted.difference(canaries) {
if _, match := canaryNames[alloc.Name]; match {
stop[id] = alloc
a.result.stop = append(a.result.stop, allocStopResult{
alloc: alloc,
statusDescription: allocNotNeeded,
})
delete(untainted, id)
remove--
if remove == 0 {
return stop
}
}
}
}
// Prefer selecting from the migrating set before stopping existing allocs
if len(migrate) != 0 {
mNames := newAllocNameIndex(a.jobID, group.Name, group.Count, migrate)
removeNames := mNames.Highest(uint(remove))
for id, alloc := range migrate {
if _, match := removeNames[alloc.Name]; !match {
continue
}
a.result.stop = append(a.result.stop, allocStopResult{
alloc: alloc,
statusDescription: allocNotNeeded,
})
delete(migrate, id)
stop[id] = alloc
nameIndex.UnsetIndex(alloc.Index())
remove--
if remove == 0 {
return stop
}
}
}
// Select the allocs with the highest count to remove
removeNames := nameIndex.Highest(uint(remove))
for id, alloc := range untainted {
if _, ok := removeNames[alloc.Name]; ok {
stop[id] = alloc
a.result.stop = append(a.result.stop, allocStopResult{
alloc: alloc,
statusDescription: allocNotNeeded,
})
delete(untainted, id)
remove--
if remove == 0 {
return stop
}
}
}
// It is possible that we didn't stop as many as we should have if there
// were allocations with duplicate names.
for id, alloc := range untainted {
stop[id] = alloc
a.result.stop = append(a.result.stop, allocStopResult{
alloc: alloc,
statusDescription: allocNotNeeded,
})
delete(untainted, id)
remove--
if remove == 0 {
return stop
}
}
return stop
}
// computeUpdates determines which allocations for the passed group require
// updates. Three groups are returned:
// 1. Those that require no upgrades
// 2. Those that can be upgraded in-place. These are added to the results
// automatically since the function contains the correct state to do so,
// 3. Those that require destructive updates
func (a *allocReconciler) computeUpdates(group *structs.TaskGroup, untainted allocSet) (ignore, inplace, destructive allocSet) {
// Determine the set of allocations that need to be updated
ignore = make(map[string]*structs.Allocation)
inplace = make(map[string]*structs.Allocation)
destructive = make(map[string]*structs.Allocation)
for _, alloc := range untainted {
ignoreChange, destructiveChange, inplaceAlloc := a.allocUpdateFn(alloc, a.job, group)
if ignoreChange {
ignore[alloc.ID] = alloc
} else if destructiveChange {
destructive[alloc.ID] = alloc
} else {
inplace[alloc.ID] = alloc
a.result.inplaceUpdate = append(a.result.inplaceUpdate, inplaceAlloc)
}
}
return
}
// handleDelayedReschedules creates batched followup evaluations with the WaitUntil field set
// for allocations that are eligible to be rescheduled later
func (a *allocReconciler) handleDelayedReschedules(rescheduleLater []*delayedRescheduleInfo, all allocSet, tgName string) {
if len(rescheduleLater) == 0 {
return
}
// Sort by time
sort.Slice(rescheduleLater, func(i, j int) bool {
return rescheduleLater[i].rescheduleTime.Before(rescheduleLater[j].rescheduleTime)
})
var evals []*structs.Evaluation
nextReschedTime := rescheduleLater[0].rescheduleTime
allocIDToFollowupEvalID := make(map[string]string, len(rescheduleLater))
// Create a new eval for the first batch
eval := &structs.Evaluation{
ID: uuid.Generate(),
Namespace: a.job.Namespace,
Priority: a.job.Priority,
Type: a.job.Type,
TriggeredBy: structs.EvalTriggerRetryFailedAlloc,
JobID: a.job.ID,
JobModifyIndex: a.job.ModifyIndex,
Status: structs.EvalStatusPending,
StatusDescription: reschedulingFollowupEvalDesc,
WaitUntil: nextReschedTime,
}
evals = append(evals, eval)
for _, allocReschedInfo := range rescheduleLater {
if allocReschedInfo.rescheduleTime.Sub(nextReschedTime) < batchedFailedAllocWindowSize {
allocIDToFollowupEvalID[allocReschedInfo.allocID] = eval.ID
} else {
// Start a new batch
nextReschedTime = allocReschedInfo.rescheduleTime
// Create a new eval for the new batch
eval = &structs.Evaluation{
ID: uuid.Generate(),
Namespace: a.job.Namespace,
Priority: a.job.Priority,
Type: a.job.Type,
TriggeredBy: structs.EvalTriggerRetryFailedAlloc,
JobID: a.job.ID,
JobModifyIndex: a.job.ModifyIndex,
Status: structs.EvalStatusPending,
WaitUntil: nextReschedTime,
}
evals = append(evals, eval)
// Set the evalID for the first alloc in this new batch
allocIDToFollowupEvalID[allocReschedInfo.allocID] = eval.ID
}
}
a.result.desiredFollowupEvals[tgName] = evals
// Initialize the annotations
if len(allocIDToFollowupEvalID) != 0 && a.result.attributeUpdates == nil {
a.result.attributeUpdates = make(map[string]*structs.Allocation)
}
// Create in-place updates for every alloc ID that needs to be updated with its follow up eval ID
for allocID, evalID := range allocIDToFollowupEvalID {
existingAlloc := all[allocID]
updatedAlloc := existingAlloc.Copy()
updatedAlloc.FollowupEvalID = evalID
a.result.attributeUpdates[updatedAlloc.ID] = updatedAlloc
}
}