-
Notifications
You must be signed in to change notification settings - Fork 2k
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
1 parent
14280e0
commit 87be0e8
Showing
4 changed files
with
144 additions
and
43 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,108 @@ | ||
| // Copyright (c) HashiCorp, Inc. | ||
| // SPDX-License-Identifier: BUSL-1.1 | ||
|
|
||
| package reconnectingpicker | ||
|
|
||
| import ( | ||
| log "github.com/hashicorp/go-hclog" | ||
| "github.com/hashicorp/nomad/nomad/structs" | ||
| ) | ||
|
|
||
| // type picker func(*structs.Allocation, *structs.Allocation) *structs.Allocation | ||
| type ReconnectingPicker struct { | ||
| logger log.Logger | ||
| } | ||
|
|
||
| func New(logger log.Logger) *ReconnectingPicker { | ||
| rp := ReconnectingPicker{ | ||
| logger: log.L().Named("reconnecting-picker"), | ||
| } | ||
|
|
||
| return &rp | ||
| } | ||
|
|
||
| func (rp *ReconnectingPicker) PickReconnectingAlloc(ds *structs.DisconnectStrategy, original *structs.Allocation, replacement *structs.Allocation) *structs.Allocation { | ||
| // Check if the replacement is newer. | ||
| // Always prefer the replacement if true. | ||
| replacementIsNewer := replacement.Job.Version > original.Job.Version || | ||
| replacement.Job.CreateIndex > original.Job.CreateIndex | ||
| if replacementIsNewer { | ||
| rp.logger.Debug("replacement has a newer version, keeping replacement") | ||
| return replacement | ||
| } | ||
|
|
||
| // Best score is the default strategy. | ||
| strategy := structs.ReconcileOptionBestScore | ||
| if ds != nil || ds.Reconcile != "" { | ||
| strategy = ds.Reconcile | ||
| } | ||
|
|
||
| rp.logger.Debug("picking according to strategy", "strategy", strategy) | ||
|
|
||
| var picker func(*structs.Allocation, *structs.Allocation) *structs.Allocation | ||
| switch strategy { | ||
| case structs.ReconcileOptionBestScore: | ||
| picker = pickBestScore | ||
|
|
||
| case structs.ReconcileOptionKeepOriginal: | ||
| picker = pickOriginal | ||
|
|
||
| case structs.ReconcileOptionKeepReplacement: | ||
| picker = pickReplacement | ||
|
|
||
| case structs.ReconcileOptionLongestRunning: | ||
| picker = pickLongestRunning | ||
| } | ||
|
|
||
| return picker(original, replacement) | ||
| } | ||
|
|
||
| // pickReconnectingAlloc returns the allocation to keep between the original | ||
| // one that is reconnecting and one of its replacements. | ||
| // | ||
| // This function is not commutative, meaning that pickReconnectingAlloc(A, B) | ||
| // is not the same as pickReconnectingAlloc(B, A). Preference is given to keep | ||
| // the original allocation when possible. | ||
| func pickBestScore(original *structs.Allocation, replacement *structs.Allocation) *structs.Allocation { | ||
|
|
||
| // Check if the replacement has better placement score. | ||
| // If any of the scores is not available, only pick the replacement if | ||
| // itself does have scores. | ||
| originalMaxScoreMeta := original.Metrics.MaxNormScore() | ||
| replacementMaxScoreMeta := replacement.Metrics.MaxNormScore() | ||
|
|
||
| replacementHasBetterScore := originalMaxScoreMeta == nil && replacementMaxScoreMeta != nil || | ||
| (originalMaxScoreMeta != nil && replacementMaxScoreMeta != nil && | ||
| replacementMaxScoreMeta.NormScore > originalMaxScoreMeta.NormScore) | ||
|
|
||
| // Check if the replacement has better client status. | ||
| // Even with a better placement score make sure we don't replace a running | ||
| // allocation with one that is not. | ||
| replacementIsRunning := replacement.ClientStatus == structs.AllocClientStatusRunning | ||
| originalNotRunning := original.ClientStatus != structs.AllocClientStatusRunning | ||
|
|
||
| if replacementHasBetterScore && (replacementIsRunning || originalNotRunning) { | ||
| return replacement | ||
| } | ||
|
|
||
| return original | ||
| } | ||
|
|
||
| func pickOriginal(original *structs.Allocation, _ *structs.Allocation) *structs.Allocation { | ||
| return original | ||
| } | ||
|
|
||
| func pickReplacement(_ *structs.Allocation, replacement *structs.Allocation) *structs.Allocation { | ||
| return replacement | ||
| } | ||
|
|
||
| func pickLongestRunning(original *structs.Allocation, replacement *structs.Allocation) *structs.Allocation { | ||
| // Check if the replacement has been running longer. | ||
| // Always prefer the replacement if true. | ||
| replacementIsLongerRunning := replacement.ClientStatus == structs.AllocClientStatusRunning | ||
| if replacementIsLongerRunning { | ||
| return replacement | ||
| } | ||
|
|
||
| return original | ||
| } |