From f34528e707720ec173c2bed0779bc24a73f6d82c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B8rn=20Erik=20Pedersen?=
 <bjorn.erik.pedersen@gmail.com>
Date: Mon, 29 Apr 2024 21:44:42 +0200
Subject: [PATCH] cache/dynacache: Don't mark all evicted items as stale

Limit that to the evicted items that matches the given change set.

Currently this doesn't make any practical difference, but it would make the stale flag more general useful.
---
 cache/dynacache/dynacache.go | 33 +++++++++++++++++----------------
 1 file changed, 17 insertions(+), 16 deletions(-)

diff --git a/cache/dynacache/dynacache.go b/cache/dynacache/dynacache.go
index 87ef68f5be2..903ec469a0b 100644
--- a/cache/dynacache/dynacache.go
+++ b/cache/dynacache/dynacache.go
@@ -74,7 +74,6 @@ func New(opts Options) *Cache {
 			evictedIdentities.Push(id)
 			return false
 		})
-		resource.MarkStale(v)
 	}
 
 	c := &Cache{
@@ -434,11 +433,8 @@ func (p *Partition[K, V]) clearMatching(predicate func(k, v any) bool) {
 
 func (p *Partition[K, V]) clearOnRebuild(changeset ...identity.Identity) {
 	opts := p.getOptions()
-	if opts.ClearWhen == ClearNever {
-		return
-	}
 
-	if opts.ClearWhen == ClearOnRebuild {
+	if opts.ClearWhen == ClearOnRebuild && len(changeset) == 0 {
 		// Clear all.
 		p.Clear()
 		return
@@ -478,17 +474,23 @@ func (p *Partition[K, V]) clearOnRebuild(changeset ...identity.Identity) {
 	// Second pass needs to be done in a separate loop to catch any
 	// elements marked as stale in the other partitions.
 	p.c.DeleteFunc(func(key K, v V) bool {
-		if shouldDelete(key, v) {
-			p.trace.Log(
-				logg.StringFunc(
-					func() string {
-						return fmt.Sprintf("first pass: clearing cache key %v", key)
-					},
-				),
-			)
-			return true
+		match := shouldDelete(key, v)
+		clear := match || opts.ClearWhen == ClearOnRebuild
+
+		if match {
+			if clear {
+				p.trace.Log(
+					logg.StringFunc(
+						func() string {
+							return fmt.Sprintf("first pass: clearing cache key %v", key)
+						},
+					),
+				)
+			}
+			resource.MarkStale(v)
 		}
-		return false
+
+		return clear
 	})
 }
 
@@ -562,7 +564,6 @@ type PartitionManager interface {
 const (
 	ClearOnRebuild ClearWhen = iota + 1
 	ClearOnChange
-	ClearNever
 )
 
 type ClearWhen int