Skip to content

reduce instance change lookups in GetResource #37154

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
jbardin merged 2 commits into from
May 22, 2025
+16 −1
Merged

reduce instance change lookups in GetResource #37154

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
f243754
reduce changes lookups in GetResource
jbardin May 22, 2025
fd6b10c
CHANGELOG
jbardin May 22, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 5 additions & 0 deletions .changes/v1.13/ENHANCEMENTS-20250522-093102.yaml
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,5 @@
kind: ENHANCEMENTS
body: Performance fix for evaluating high cardinality resources
time: 2025-05-22T09:31:02.761383-04:00
custom:
Issue: "26355"
12 changes: 11 additions & 1 deletion internal/terraform/evaluate.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -658,6 +658,16 @@ func (d *evaluationStateData) GetResource(addr addrs.Resource, rng tfdiags.Sourc
instances[key] = value
}

// Proactively read out all the resource changes before iteration. Not only
// does GetResourceInstanceChange have to iterate over all instances
// internally causing an n^2 lookup, but Changes is also a major point of
// lock contention.
resChanges := d.Evaluator.Changes.GetChangesForConfigResource(addr.InModule(moduleConfig.Path))
instChanges := addrs.MakeMap[addrs.AbsResourceInstance, *plans.ResourceInstanceChange]()
for _, ch := range resChanges {
instChanges.Put(ch.Addr, ch)
}

// Decode all instances in the current state
pendingDestroy := d.Operation == walkDestroy
for key, is := range rs.Instances {
Expand All @@ -675,7 +685,7 @@ func (d *evaluationStateData) GetResource(addr addrs.Resource, rng tfdiags.Sourc
}

instAddr := addr.Instance(key).Absolute(d.ModulePath)
change := d.Evaluator.Changes.GetResourceInstanceChange(instAddr, addrs.NotDeposed)
change := instChanges.Get(instAddr)
if change != nil {
// Don't take any resources that are yet to be deleted into account.
// If the referenced resource is CreateBeforeDestroy, then orphaned
Expand Down