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Diffstat (limited to 'internal/flamegraph')
-rw-r--r--internal/flamegraph/livetrie.go65
-rw-r--r--internal/flamegraph/livetrie_test.go12
2 files changed, 58 insertions, 19 deletions
diff --git a/internal/flamegraph/livetrie.go b/internal/flamegraph/livetrie.go
index 51f3697..5487b9f 100644
--- a/internal/flamegraph/livetrie.go
+++ b/internal/flamegraph/livetrie.go
@@ -19,11 +19,11 @@ const (
liveTrieVisibleChildrenFallbackMaxDepth = 1
)
-type trieSnapshot struct {
+type SnapshotNode struct {
Name string `json:"n"`
Value uint64 `json:"v"`
Total uint64 `json:"t"`
- Children []*trieSnapshot `json:"c,omitempty"`
+ Children []*SnapshotNode `json:"c,omitempty"`
}
// LiveTrie is a thread-safe, append-only trie used for live flamegraph snapshots.
@@ -39,6 +39,13 @@ type LiveTrie struct {
cacheMu sync.Mutex
cacheVersion uint64
cacheJSON []byte
+
+ // Tree cache lets the TUI fetch the snapshot tree without a JSON
+ // marshal+unmarshal round-trip. Built lazily; invalidated on reset and
+ // on field/metric reconfiguration.
+ treeCacheMu sync.Mutex
+ treeVersion uint64
+ treeCache *SnapshotNode
}
// NewLiveTrie constructs an empty live trie with the configured frame/count fields.
@@ -75,6 +82,10 @@ func (lt *LiveTrie) invalidateCache() {
lt.cacheVersion = 0
lt.cacheJSON = nil
lt.cacheMu.Unlock()
+ lt.treeCacheMu.Lock()
+ lt.treeVersion = 0
+ lt.treeCache = nil
+ lt.treeCacheMu.Unlock()
}
// Ingest adds one event pair into the live trie.
@@ -161,6 +172,8 @@ func (lt *LiveTrie) Version() uint64 {
}
// SnapshotJSON returns a compact JSON snapshot for the current trie version.
+// Layered on top of SnapshotTree so the tree-building work is shared with
+// callers that want the typed form directly.
func (lt *LiveTrie) SnapshotJSON() ([]byte, uint64) {
version := lt.Version()
lt.cacheMu.Lock()
@@ -171,12 +184,7 @@ func (lt *LiveTrie) SnapshotJSON() ([]byte, uint64) {
}
lt.cacheMu.Unlock()
- lt.mu.RLock()
- version = lt.version.Load()
- rootTotal := subtreeTotal(lt.root)
- snapshot := buildSnapshot(lt.root, 0, liveTrieMinFraction, rootTotal)
- lt.mu.RUnlock()
-
+ snapshot, version := lt.SnapshotTree()
payload, err := json.Marshal(snapshot)
if err != nil {
return []byte(`{}`), version
@@ -190,6 +198,37 @@ func (lt *LiveTrie) SnapshotJSON() ([]byte, uint64) {
return payload, version
}
+// SnapshotTree returns the live trie snapshot as a typed node tree, bypassing
+// the JSON round-trip. The pointer is safe to retain — buildSnapshot allocates
+// fresh nodes per snapshot, and the trie never mutates a previously returned
+// tree. The TUI uses this on a background goroutine so per-tick refreshes don't
+// block the Bubble Tea update loop.
+func (lt *LiveTrie) SnapshotTree() (*SnapshotNode, uint64) {
+ version := lt.Version()
+ lt.treeCacheMu.Lock()
+ if lt.treeVersion == version && lt.treeCache != nil {
+ tree := lt.treeCache
+ lt.treeCacheMu.Unlock()
+ return tree, version
+ }
+ lt.treeCacheMu.Unlock()
+
+ lt.mu.RLock()
+ version = lt.version.Load()
+ rootTotal := subtreeTotal(lt.root)
+ tree := buildSnapshot(lt.root, 0, liveTrieMinFraction, rootTotal)
+ lt.mu.RUnlock()
+
+ lt.treeCacheMu.Lock()
+ // Only commit if no concurrent caller stored a newer version.
+ if version >= lt.treeVersion {
+ lt.treeVersion = version
+ lt.treeCache = tree
+ }
+ lt.treeCacheMu.Unlock()
+ return tree, version
+}
+
func eventPairToRecord(ep *event.Pair) IterRecord {
return IterRecord{
Path: ep.FileName(),
@@ -263,18 +302,18 @@ func subtreeTotal(node *trieNode) uint64 {
return total
}
-func buildSnapshot(node *trieNode, depth int, minFraction float64, rootTotal uint64) *trieSnapshot {
+func buildSnapshot(node *trieNode, depth int, minFraction float64, rootTotal uint64) *SnapshotNode {
snapshot, _ := buildSnapshotWithTotal(node, depth, minFraction, rootTotal, false)
return snapshot
}
type childSnapshotState struct {
node *trieNode
- snapshot *trieSnapshot
+ snapshot *SnapshotNode
total uint64
}
-func buildSnapshotWithTotal(node *trieNode, depth int, minFraction float64, rootTotal uint64, forceKeep bool) (*trieSnapshot, uint64) {
+func buildSnapshotWithTotal(node *trieNode, depth int, minFraction float64, rootTotal uint64, forceKeep bool) (*SnapshotNode, uint64) {
total := node.value
children := slices.Clone(node.children)
slices.SortFunc(children, func(a, b *trieNode) int {
@@ -297,14 +336,14 @@ func buildSnapshotWithTotal(node *trieNode, depth int, minFraction float64, root
}
ensureFallbackVisibleChildren(childStates, depth, minFraction, rootTotal)
- childSnapshots := make([]*trieSnapshot, 0, len(childStates))
+ childSnapshots := make([]*SnapshotNode, 0, len(childStates))
for _, child := range childStates {
if child.snapshot != nil {
childSnapshots = append(childSnapshots, child.snapshot)
}
}
- snapshot := &trieSnapshot{
+ snapshot := &SnapshotNode{
Name: node.name,
Value: node.value,
Total: total,
diff --git a/internal/flamegraph/livetrie_test.go b/internal/flamegraph/livetrie_test.go
index 5d4ce47..6a825c0 100644
--- a/internal/flamegraph/livetrie_test.go
+++ b/internal/flamegraph/livetrie_test.go
@@ -371,7 +371,7 @@ func TestLiveTrieConcurrentIngestAndSnapshot(t *testing.T) {
defer wg.Done()
for i := 0; i < 500; i++ {
payload, _ := lt.SnapshotJSON()
- var snap trieSnapshot
+ var snap SnapshotNode
if err := json.Unmarshal(payload, &snap); err != nil {
t.Errorf("unmarshal snapshot: %v", err)
return
@@ -416,7 +416,7 @@ func TestLiveTrieStressHighRateConcurrentSnapshot(t *testing.T) {
return
case <-ticker.C:
payload, _ := lt.SnapshotJSON()
- var snap trieSnapshot
+ var snap SnapshotNode
if err := json.Unmarshal(payload, &snap); err != nil {
errCh <- fmt.Errorf("snapshot json invalid: %w", err)
return
@@ -486,17 +486,17 @@ func newTestPair(comm string, pid uint32, tid uint32, path string, duration uint
return pair
}
-func decodeLiveSnapshot(t *testing.T, lt *LiveTrie) trieSnapshot {
+func decodeLiveSnapshot(t *testing.T, lt *LiveTrie) SnapshotNode {
t.Helper()
payload, _ := lt.SnapshotJSON()
- var snap trieSnapshot
+ var snap SnapshotNode
if err := json.Unmarshal(payload, &snap); err != nil {
t.Fatalf("unmarshal snapshot: %v", err)
}
return snap
}
-func findSnapshotPath(t *testing.T, root *trieSnapshot, names ...string) *trieSnapshot {
+func findSnapshotPath(t *testing.T, root *SnapshotNode, names ...string) *SnapshotNode {
t.Helper()
node := root
for _, name := range names {
@@ -508,7 +508,7 @@ func findSnapshotPath(t *testing.T, root *trieSnapshot, names ...string) *trieSn
return node
}
-func findSnapshotChild(node *trieSnapshot, name string) *trieSnapshot {
+func findSnapshotChild(node *SnapshotNode, name string) *SnapshotNode {
for _, child := range node.Children {
if child.Name == name {
return child
generated by cgit v1.2.3 (git 2.25.1) at 2026-06-16 17:44:27 +0000