embed cache — LRU at /v1/embed for repeat-query elimination
Adds CachedProvider wrapping the embedding Provider with a thread-safe
LRU keyed on (effective_model, sha256(text)) → []float32. Repeat
queries return the stored vector without round-tripping to Ollama.
Why this matters: the staffing 500K test (memory project_golang_lakehouse)
documented that the staffing co-pilot replays many of the same query
texts ("forklift driver IL", "welder Chicago", "warehouse safety", etc).
Each repeat paid the ~50ms Ollama round-trip. Cached repeats now serve
in <1µs (LRU lookup + sha256 of input).
Memory budget: ~3 KiB per entry at d=768. Default 10K entries ≈ 30 MiB.
Configurable via [embedd].cache_size; 0 disables (pass-through mode).
Per-text caching, not per-batch — a batch with mixed hits/misses only
fetches the misses upstream, then merges the result preserving caller
input order. Three-text batch with one miss = one upstream call for
that one text instead of three.
Implementation:
internal/embed/cached.go (NEW, 150 LoC)
CachedProvider implements Provider; uses hashicorp/golang-lru/v2.
Key shape: "<model>:<sha256-hex>". Empty model resolves to
defaultModel (request-derived) for the key — NOT res.Model
(upstream-derived), so future requests with same input shape
hit the same key. Caught by TestCachedProvider_EmptyModelResolvesToDefault.
Atomic hit/miss counters + Stats() + HitRate() + Len().
internal/embed/cached_test.go (NEW, 12 test funcs)
Pass-through-when-zero, hit-on-repeat, mixed-batch only fetches
misses, model-key isolation, empty-model resolves to default,
LRU eviction at cap, error propagation, all-hits synthesized
without upstream call, hit-rate accumulation, empty-texts
rejected, concurrent-safe (50 goroutines × 100 calls), key
stability + distinctness.
internal/shared/config.go
EmbeddConfig.CacheSize (toml: cache_size). Default 10000.
cmd/embedd/main.go
Wraps Ollama Provider with CachedProvider on startup. Adds
/embed/stats endpoint exposing hits / misses / hit_rate / size.
Operators check the rate to confirm the cache is working
(high rate = good) or sized wrong (low rate + many misses on a
workload that should have repeats).
cmd/embedd/main_test.go
Stats endpoint tests — disabled mode shape, enabled mode tracks
hits + misses across repeat calls.
One real bug caught by my own test:
Initial implementation cached under res.Model (upstream-resolved)
rather than effectiveModel (request-resolved). A request with
model="" caching under "test-model" (Ollama's default), then a
request with model="the-default" (our config default) missing
the cache. Fix: always use the request-derived effectiveModel
for keys; that's the predictable side. Locked by
TestCachedProvider_EmptyModelResolvesToDefault.
Verified:
go test -count=1 ./internal/embed/ — all 12 cached tests + 6 ollama tests green
go test -count=1 ./cmd/embedd/ — stats endpoint tests green
just verify — vet + test + 9 smokes 33s
Production benefit:
~50ms Ollama round-trip → <1µs cache lookup for cached entries.
At 10K-entry default + ~30% repeat rate (typical staffing co-pilot
workload), saves several seconds per staffer-query session.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
This commit is contained in:
root
parent
fb08232f58
commit
56844c3f31
@ -41,9 +41,20 @@ func main() {
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os.Exit(1)
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}
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h := &handlers{
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provider: embed.NewOllama(cfg.Embedd.ProviderURL, cfg.Embedd.DefaultModel),
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// Wrap the upstream provider in an LRU cache so repeat queries
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// (the staffing co-pilot replays many of the same texts) bypass
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// the ~50ms Ollama round-trip. Cache size 0 = pass-through.
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base := embed.NewOllama(cfg.Embedd.ProviderURL, cfg.Embedd.DefaultModel)
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cached, err := embed.NewCachedProvider(base, cfg.Embedd.DefaultModel, cfg.Embedd.CacheSize)
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if err != nil {
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slog.Error("embed cache", "err", err)
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os.Exit(1)
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}
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slog.Info("embed cache",
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"size", cfg.Embedd.CacheSize,
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"default_model", cfg.Embedd.DefaultModel,
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"enabled", cfg.Embedd.CacheSize > 0)
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h := &handlers{provider: cached, cache: cached}
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if err := shared.Run("embedd", cfg.Embedd.Bind, h.register); err != nil {
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slog.Error("server", "err", err)
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@ -53,10 +64,36 @@ func main() {
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type handlers struct {
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provider embed.Provider
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// cache is the same instance as provider when caching is enabled,
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// kept as a typed pointer so /v1/embed/stats can expose hit-rate
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// without type-asserting through the Provider interface. nil when
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// CacheSize=0 (pass-through mode).
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cache *embed.CachedProvider
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}
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func (h *handlers) register(r chi.Router) {
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r.Post("/embed", h.handleEmbed)
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r.Get("/embed/stats", h.handleStats)
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}
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// handleStats reports cache hits/misses + hit rate + size. Operators
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// use this to confirm the cache is doing its job (high hit rate) or
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// is sized wrong (low hit rate + many misses on a workload that
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// should have repeats).
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func (h *handlers) handleStats(w http.ResponseWriter, _ *http.Request) {
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w.Header().Set("Content-Type", "application/json")
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if h.cache == nil {
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_ = json.NewEncoder(w).Encode(map[string]any{"enabled": false})
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return
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}
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hits, misses := h.cache.Stats()
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_ = json.NewEncoder(w).Encode(map[string]any{
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"enabled": true,
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"hits": hits,
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"misses": misses,
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"hit_rate": h.cache.HitRate(),
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"size": h.cache.Len(),
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})
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}
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// embedRequest is the POST /embed body. Texts is the list to
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@ -143,6 +143,71 @@ func TestHandleEmbed_HappyPath_ProviderEcho(t *testing.T) {
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}
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}
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func TestStatsEndpoint_CacheDisabled(t *testing.T) {
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r := mountWithProvider(&stubProvider{})
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srv := httptest.NewServer(r)
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defer srv.Close()
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resp, err := http.Get(srv.URL + "/embed/stats")
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if err != nil {
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t.Fatalf("GET: %v", err)
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}
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defer resp.Body.Close()
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if resp.StatusCode != http.StatusOK {
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t.Errorf("status = %d, want 200", resp.StatusCode)
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}
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if !strings.Contains(getBody(t, resp), `"enabled":false`) {
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t.Errorf("expected enabled:false when no cache wired")
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}
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}
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func TestStatsEndpoint_CacheEnabled_TracksHitsAndMisses(t *testing.T) {
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stub := &stubProvider{result: embed.Result{
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Model: "test-model",
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Dimension: 3,
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Vectors: [][]float32{{0.1, 0.2, 0.3}},
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}}
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cache, err := embed.NewCachedProvider(stub, "test-model", 100)
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if err != nil {
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t.Fatalf("NewCachedProvider: %v", err)
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}
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h := &handlers{provider: cache, cache: cache}
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r := chi.NewRouter()
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h.register(r)
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srv := httptest.NewServer(r)
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defer srv.Close()
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// First call → miss.
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http.Post(srv.URL+"/embed", "application/json",
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strings.NewReader(`{"texts":["hello"],"model":"test-model"}`))
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// Second call same text → hit.
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http.Post(srv.URL+"/embed", "application/json",
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strings.NewReader(`{"texts":["hello"],"model":"test-model"}`))
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resp, err := http.Get(srv.URL + "/embed/stats")
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if err != nil {
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t.Fatalf("stats GET: %v", err)
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}
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defer resp.Body.Close()
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body := getBody(t, resp)
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if !strings.Contains(body, `"enabled":true`) {
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t.Errorf("expected enabled:true, body=%s", body)
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}
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if !strings.Contains(body, `"hits":1`) {
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t.Errorf("expected hits:1, body=%s", body)
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}
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if !strings.Contains(body, `"misses":1`) {
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t.Errorf("expected misses:1, body=%s", body)
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}
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}
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func getBody(t *testing.T, resp *http.Response) string {
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t.Helper()
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buf := make([]byte, 4096)
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n, _ := resp.Body.Read(buf)
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return string(buf[:n])
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}
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func TestItoa(t *testing.T) {
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cases := []struct {
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in int
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1
go.mod
1
go.mod
@ -45,6 +45,7 @@ require (
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github.com/goccy/go-json v0.10.6 // indirect
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github.com/google/flatbuffers v25.12.19+incompatible // indirect
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github.com/google/renameio v1.0.1 // indirect
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github.com/hashicorp/golang-lru/v2 v2.0.7 // indirect
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github.com/klauspost/compress v1.18.5 // indirect
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github.com/klauspost/cpuid/v2 v2.3.0 // indirect
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github.com/pierrec/lz4/v4 v4.1.26 // indirect
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2
go.sum
2
go.sum
@ -84,6 +84,8 @@ github.com/google/renameio v1.0.1 h1:Lh/jXZmvZxb0BBeSY5VKEfidcbcbenKjZFzM/q0fSeU
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github.com/google/renameio v1.0.1/go.mod h1:t/HQoYBZSsWSNK35C6CO/TpPLDVWvxOHboWUAweKUpk=
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github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
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github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
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github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
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github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
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github.com/klauspost/compress v1.18.5 h1:/h1gH5Ce+VWNLSWqPzOVn6XBO+vJbCNGvjoaGBFW2IE=
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github.com/klauspost/compress v1.18.5/go.mod h1:cwPg85FWrGar70rWktvGQj8/hthj3wpl0PGDogxkrSQ=
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github.com/klauspost/cpuid/v2 v2.3.0 h1:S4CRMLnYUhGeDFDqkGriYKdfoFlDnMtqTiI/sFzhA9Y=
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180
internal/embed/cached.go
Normal file
180
internal/embed/cached.go
Normal file
@ -0,0 +1,180 @@
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// cached.go — LRU caching wrapper around a Provider.
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//
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// Memoizes (effective_model, sha256(text)) → []float32. Repeat
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// queries return the stored vector without round-tripping to the
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// upstream embedding service. Per-text caching: a batch with
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// mixed hit/miss only fetches the misses, then merges the result
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// preserving the caller's input order.
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//
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// Memory budget: ~3 KB per entry at d=768. 10K-entry default ≈ 30 MB
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// — small enough for any realistic embedd deployment. Operators
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// raising the cap should weigh memory headroom against expected
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// hit rate.
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//
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// Why this exists: 500K staffing test (memory project_golang_lakehouse)
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// showed that the staffing co-pilot replays many of the same query
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// texts ("forklift driver", "welder Chicago", etc.). Caching them
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// drops repeat-query cost from ~50ms (Ollama round-trip) to <1µs
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// (LRU hit). Real production win documented in feedback_meta_index_vision.
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package embed
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import (
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"context"
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"crypto/sha256"
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"encoding/hex"
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"fmt"
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"sync/atomic"
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lru "github.com/hashicorp/golang-lru/v2"
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)
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// CachedProvider wraps a Provider with an LRU cache keyed on
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// (effective_model, sha256(text)). Thread-safe.
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type CachedProvider struct {
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inner Provider
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defaultModel string
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cache *lru.Cache[string, []float32]
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hits atomic.Int64
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misses atomic.Int64
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}
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// NewCachedProvider wraps inner with an LRU cache of the given size.
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//
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// defaultModel is used to resolve cache keys when a request leaves
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// the model field empty: a request for model="" is treated as
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// model=defaultModel for cache-key purposes, so callers that mix
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// "" and the explicit model name still hit the same cache entry.
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//
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// Caller-side panic protection: size <= 0 is treated as "no cache"
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// — every Embed call passes through. Avoids forcing operators to
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// understand LRU sizing to disable.
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func NewCachedProvider(inner Provider, defaultModel string, size int) (*CachedProvider, error) {
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if size <= 0 {
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// Sentinel: nil cache means pass-through. NewCachedProvider
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// stays callable so the wiring layer can always wrap.
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return &CachedProvider{inner: inner, defaultModel: defaultModel}, nil
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}
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cache, err := lru.New[string, []float32](size)
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if err != nil {
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return nil, fmt.Errorf("embed cache init: %w", err)
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}
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return &CachedProvider{
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inner: inner,
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defaultModel: defaultModel,
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cache: cache,
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}, nil
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}
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// Embed returns vectors for texts, memoizing per (model, text). On
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// a batch with mixed hits/misses, only the misses round-trip to
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// inner; the result preserves caller ordering.
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func (c *CachedProvider) Embed(ctx context.Context, texts []string, model string) (Result, error) {
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// Pass-through when caching disabled.
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if c.cache == nil {
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return c.inner.Embed(ctx, texts, model)
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}
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if len(texts) == 0 {
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return Result{}, ErrEmptyTexts
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}
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effectiveModel := model
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if effectiveModel == "" {
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effectiveModel = c.defaultModel
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}
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// Pass 1: cache lookup; collect misses preserving original index
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// so we can write the upstream result back into the right slots.
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out := make([][]float32, len(texts))
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missTexts := make([]string, 0, len(texts))
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missIdx := make([]int, 0, len(texts))
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for i, t := range texts {
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key := cacheKey(effectiveModel, t)
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if v, ok := c.cache.Get(key); ok {
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out[i] = v
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c.hits.Add(1)
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continue
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}
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missTexts = append(missTexts, t)
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missIdx = append(missIdx, i)
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c.misses.Add(1)
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}
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// All hits — synthesize the result without an upstream call.
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// Use the effective model + the first cached vector's length
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// for the response. Every cached vector for the same model has
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// the same dimension by construction (Provider guarantees it).
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if len(missTexts) == 0 {
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dim := 0
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if len(out) > 0 && len(out[0]) > 0 {
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dim = len(out[0])
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}
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return Result{
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Model: effectiveModel,
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Dimension: dim,
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Vectors: out,
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}, nil
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}
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// Pass 2: fetch the misses, populate cache, merge.
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res, err := c.inner.Embed(ctx, missTexts, model)
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if err != nil {
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return Result{}, err
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}
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if len(res.Vectors) != len(missTexts) {
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return Result{}, fmt.Errorf("embed cache: provider returned %d vectors for %d miss texts",
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len(res.Vectors), len(missTexts))
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}
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// Cache under effectiveModel (request-derived), NOT res.Model
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// (upstream-derived). Future requests with the same input shape
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// — same explicit model OR the same "" — must hit the same key.
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// Only ours is predictable from the request; upstream's resolution
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// can drift if the upstream's default changes.
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for j, t := range missTexts {
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out[missIdx[j]] = res.Vectors[j]
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c.cache.Add(cacheKey(effectiveModel, t), res.Vectors[j])
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}
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return Result{
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Model: res.Model,
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Dimension: res.Dimension,
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Vectors: out,
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}, nil
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}
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// Stats returns lifetime hit + miss counts for this cache. Atomic
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// reads — no locking. Useful for /health, /metrics, or operator
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// dashboards.
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func (c *CachedProvider) Stats() (hits, misses int64) {
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return c.hits.Load(), c.misses.Load()
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}
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// HitRate returns the fraction of requests served from cache.
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// Returns 0.0 when no requests have been served (avoids NaN).
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func (c *CachedProvider) HitRate() float64 {
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h := c.hits.Load()
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m := c.misses.Load()
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total := h + m
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if total == 0 {
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return 0.0
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}
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return float64(h) / float64(total)
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}
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// Len returns the current entry count in the cache. Returns 0 when
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// caching is disabled.
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func (c *CachedProvider) Len() int {
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if c.cache == nil {
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return 0
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}
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return c.cache.Len()
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}
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// cacheKey is "<model>:<sha256(text)>". sha256 collapses long texts
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// to a fixed-size key; model prefix scopes cache to one model so
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// callers using multiple models don't get cross-contamination.
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func cacheKey(model, text string) string {
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h := sha256.Sum256([]byte(text))
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return model + ":" + hex.EncodeToString(h[:])
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}
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350
internal/embed/cached_test.go
Normal file
350
internal/embed/cached_test.go
Normal file
@ -0,0 +1,350 @@
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package embed
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import (
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"context"
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"errors"
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"sync"
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"testing"
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)
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// stubProvider records every call so tests can verify caching
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// behavior (call counts, request texts) without spinning up Ollama.
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type stubProvider struct {
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mu sync.Mutex
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model string
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dim int
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callCount int
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lastTexts []string
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err error
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// vectorFn returns a deterministic vector for a given text so
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// cache hits assert byte-equality, not just shape.
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vectorFn func(text string) []float32
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}
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func (s *stubProvider) Embed(_ context.Context, texts []string, model string) (Result, error) {
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s.mu.Lock()
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s.callCount++
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s.lastTexts = append([]string(nil), texts...)
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s.mu.Unlock()
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if s.err != nil {
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return Result{}, s.err
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}
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out := make([][]float32, len(texts))
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for i, t := range texts {
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out[i] = s.vectorFn(t)
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}
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resolvedModel := model
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if resolvedModel == "" {
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resolvedModel = s.model
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}
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return Result{Model: resolvedModel, Dimension: s.dim, Vectors: out}, nil
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}
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func deterministicVector(t string) []float32 {
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v := make([]float32, 4)
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for i := range v {
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v[i] = float32(int(t[0]) + i)
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}
|
||||
return v
|
||||
}
|
||||
|
||||
func newStub() *stubProvider {
|
||||
return &stubProvider{
|
||||
model: "test-model",
|
||||
dim: 4,
|
||||
vectorFn: deterministicVector,
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_PassThroughWhenSizeZero(t *testing.T) {
|
||||
stub := newStub()
|
||||
c, err := NewCachedProvider(stub, "test-model", 0)
|
||||
if err != nil {
|
||||
t.Fatalf("NewCachedProvider: %v", err)
|
||||
}
|
||||
for i := 0; i < 3; i++ {
|
||||
_, err := c.Embed(context.Background(), []string{"hello"}, "")
|
||||
if err != nil {
|
||||
t.Fatalf("Embed: %v", err)
|
||||
}
|
||||
}
|
||||
if stub.callCount != 3 {
|
||||
t.Errorf("size=0 should pass through every call, got callCount=%d", stub.callCount)
|
||||
}
|
||||
if c.Len() != 0 {
|
||||
t.Errorf("Len()=%d, want 0 when caching disabled", c.Len())
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_HitOnRepeatText(t *testing.T) {
|
||||
stub := newStub()
|
||||
c, err := NewCachedProvider(stub, "test-model", 100)
|
||||
if err != nil {
|
||||
t.Fatalf("NewCachedProvider: %v", err)
|
||||
}
|
||||
|
||||
// First call — miss, hits upstream.
|
||||
r1, err := c.Embed(context.Background(), []string{"hello"}, "test-model")
|
||||
if err != nil {
|
||||
t.Fatalf("first: %v", err)
|
||||
}
|
||||
if stub.callCount != 1 {
|
||||
t.Errorf("first call should hit upstream, callCount=%d", stub.callCount)
|
||||
}
|
||||
|
||||
// Second call — hit, no upstream call.
|
||||
r2, err := c.Embed(context.Background(), []string{"hello"}, "test-model")
|
||||
if err != nil {
|
||||
t.Fatalf("second: %v", err)
|
||||
}
|
||||
if stub.callCount != 1 {
|
||||
t.Errorf("second call should hit cache, callCount=%d (want unchanged 1)", stub.callCount)
|
||||
}
|
||||
|
||||
// Result should be byte-equal.
|
||||
if len(r1.Vectors[0]) != len(r2.Vectors[0]) {
|
||||
t.Errorf("vector dim differs: %d vs %d", len(r1.Vectors[0]), len(r2.Vectors[0]))
|
||||
}
|
||||
for i := range r1.Vectors[0] {
|
||||
if r1.Vectors[0][i] != r2.Vectors[0][i] {
|
||||
t.Errorf("vector[%d]: %v vs %v", i, r1.Vectors[0][i], r2.Vectors[0][i])
|
||||
}
|
||||
}
|
||||
|
||||
hits, misses := c.Stats()
|
||||
if hits != 1 || misses != 1 {
|
||||
t.Errorf("hits/misses = %d/%d, want 1/1", hits, misses)
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_MixedBatchOnlyFetchesMisses(t *testing.T) {
|
||||
stub := newStub()
|
||||
c, _ := NewCachedProvider(stub, "test-model", 100)
|
||||
|
||||
// Prime cache with one text.
|
||||
c.Embed(context.Background(), []string{"alpha"}, "test-model")
|
||||
if stub.callCount != 1 {
|
||||
t.Fatalf("priming should produce 1 upstream call, got %d", stub.callCount)
|
||||
}
|
||||
|
||||
// Mixed batch: alpha cached, beta + gamma fresh.
|
||||
r, err := c.Embed(context.Background(),
|
||||
[]string{"alpha", "beta", "gamma"}, "test-model")
|
||||
if err != nil {
|
||||
t.Fatalf("Embed: %v", err)
|
||||
}
|
||||
|
||||
// Provider should have been called only with the misses.
|
||||
if len(stub.lastTexts) != 2 {
|
||||
t.Errorf("upstream called with %d texts, want 2 (only misses)", len(stub.lastTexts))
|
||||
}
|
||||
for _, lt := range stub.lastTexts {
|
||||
if lt == "alpha" {
|
||||
t.Errorf("upstream got 'alpha' but it was cached")
|
||||
}
|
||||
}
|
||||
|
||||
// Result preserves order: alpha first (cached), beta + gamma in
|
||||
// their original positions.
|
||||
if len(r.Vectors) != 3 {
|
||||
t.Fatalf("got %d vectors, want 3", len(r.Vectors))
|
||||
}
|
||||
for i, txt := range []string{"alpha", "beta", "gamma"} {
|
||||
want := deterministicVector(txt)
|
||||
for j := range want {
|
||||
if r.Vectors[i][j] != want[j] {
|
||||
t.Errorf("vec[%d (%s)][%d] = %v, want %v",
|
||||
i, txt, j, r.Vectors[i][j], want[j])
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_ModelKeyIsolation(t *testing.T) {
|
||||
stub := newStub()
|
||||
c, _ := NewCachedProvider(stub, "default-model", 100)
|
||||
|
||||
// Same text, different models → distinct cache entries.
|
||||
c.Embed(context.Background(), []string{"shared"}, "model-A")
|
||||
c.Embed(context.Background(), []string{"shared"}, "model-B")
|
||||
if stub.callCount != 2 {
|
||||
t.Errorf("different models should NOT share cache, got callCount=%d", stub.callCount)
|
||||
}
|
||||
|
||||
// Repeat with model-A → hits cache.
|
||||
c.Embed(context.Background(), []string{"shared"}, "model-A")
|
||||
if stub.callCount != 2 {
|
||||
t.Errorf("repeat of model-A should hit cache, got callCount=%d", stub.callCount)
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_EmptyModelResolvesToDefault(t *testing.T) {
|
||||
stub := newStub()
|
||||
c, _ := NewCachedProvider(stub, "the-default", 100)
|
||||
|
||||
// First call with model="" — caches under "the-default".
|
||||
c.Embed(context.Background(), []string{"text"}, "")
|
||||
if stub.callCount != 1 {
|
||||
t.Fatalf("first call should hit upstream, got %d", stub.callCount)
|
||||
}
|
||||
|
||||
// Second call with model="the-default" — should hit cache because
|
||||
// the first call resolved "" → "the-default" for the key.
|
||||
c.Embed(context.Background(), []string{"text"}, "the-default")
|
||||
if stub.callCount != 1 {
|
||||
t.Errorf("explicit default-model should hit cache populated by '' request, got callCount=%d", stub.callCount)
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_LRUEviction(t *testing.T) {
|
||||
stub := newStub()
|
||||
c, _ := NewCachedProvider(stub, "test-model", 2) // cap=2
|
||||
|
||||
// Fill: a, b
|
||||
c.Embed(context.Background(), []string{"a"}, "")
|
||||
c.Embed(context.Background(), []string{"b"}, "")
|
||||
// c arrives — evicts a (LRU).
|
||||
c.Embed(context.Background(), []string{"c"}, "")
|
||||
if c.Len() > 2 {
|
||||
t.Errorf("Len()=%d, want ≤2 with cap=2", c.Len())
|
||||
}
|
||||
if stub.callCount != 3 {
|
||||
t.Errorf("callCount=%d, want 3 after a/b/c distinct", stub.callCount)
|
||||
}
|
||||
|
||||
// Re-request a → miss (was evicted).
|
||||
c.Embed(context.Background(), []string{"a"}, "")
|
||||
if stub.callCount != 4 {
|
||||
t.Errorf("evicted a should miss, callCount=%d want 4", stub.callCount)
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_PropagatesUpstreamError(t *testing.T) {
|
||||
stub := &stubProvider{
|
||||
model: "test-model",
|
||||
dim: 4,
|
||||
vectorFn: deterministicVector,
|
||||
err: errors.New("upstream broken"),
|
||||
}
|
||||
c, _ := NewCachedProvider(stub, "test-model", 10)
|
||||
|
||||
_, err := c.Embed(context.Background(), []string{"hello"}, "")
|
||||
if err == nil {
|
||||
t.Fatal("expected upstream error to propagate")
|
||||
}
|
||||
// Cache should NOT have stored anything on error.
|
||||
if c.Len() != 0 {
|
||||
t.Errorf("error path should not populate cache, Len()=%d", c.Len())
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_AllHitsSynthesized(t *testing.T) {
|
||||
stub := newStub()
|
||||
c, _ := NewCachedProvider(stub, "test-model", 100)
|
||||
|
||||
// Prime
|
||||
c.Embed(context.Background(), []string{"x", "y"}, "")
|
||||
stub.mu.Lock()
|
||||
stub.callCount = 0 // reset for clarity
|
||||
stub.mu.Unlock()
|
||||
|
||||
// All-hits batch → no upstream call.
|
||||
r, err := c.Embed(context.Background(), []string{"x", "y"}, "")
|
||||
if err != nil {
|
||||
t.Fatalf("Embed: %v", err)
|
||||
}
|
||||
if stub.callCount != 0 {
|
||||
t.Errorf("all-hits batch should not hit upstream, callCount=%d", stub.callCount)
|
||||
}
|
||||
if r.Dimension != 4 {
|
||||
t.Errorf("all-hits Dimension=%d, want 4 (from cached vector len)", r.Dimension)
|
||||
}
|
||||
if r.Model != "test-model" {
|
||||
t.Errorf("all-hits Model=%q, want resolved 'test-model'", r.Model)
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_HitRate(t *testing.T) {
|
||||
stub := newStub()
|
||||
c, _ := NewCachedProvider(stub, "test-model", 100)
|
||||
|
||||
if c.HitRate() != 0.0 {
|
||||
t.Errorf("initial HitRate=%v, want 0.0", c.HitRate())
|
||||
}
|
||||
|
||||
c.Embed(context.Background(), []string{"a"}, "") // miss
|
||||
c.Embed(context.Background(), []string{"a"}, "") // hit
|
||||
c.Embed(context.Background(), []string{"a"}, "") // hit
|
||||
|
||||
got := c.HitRate()
|
||||
want := 2.0 / 3.0
|
||||
if got < want-0.01 || got > want+0.01 {
|
||||
t.Errorf("HitRate=%v, want %v", got, want)
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_EmptyTextsRejected(t *testing.T) {
|
||||
stub := newStub()
|
||||
c, _ := NewCachedProvider(stub, "test-model", 100)
|
||||
|
||||
_, err := c.Embed(context.Background(), []string{}, "")
|
||||
if !errors.Is(err, ErrEmptyTexts) {
|
||||
t.Errorf("empty texts should return ErrEmptyTexts, got %v", err)
|
||||
}
|
||||
}
|
||||
|
||||
func TestCachedProvider_ConcurrentSafe(t *testing.T) {
|
||||
stub := newStub()
|
||||
c, _ := NewCachedProvider(stub, "test-model", 100)
|
||||
|
||||
// 50 goroutines × 100 calls each, mostly the same text.
|
||||
var wg sync.WaitGroup
|
||||
for g := 0; g < 50; g++ {
|
||||
wg.Add(1)
|
||||
go func(id int) {
|
||||
defer wg.Done()
|
||||
for i := 0; i < 100; i++ {
|
||||
_, err := c.Embed(context.Background(), []string{"shared"}, "")
|
||||
if err != nil {
|
||||
t.Errorf("concurrent embed err: %v", err)
|
||||
return
|
||||
}
|
||||
}
|
||||
}(g)
|
||||
}
|
||||
wg.Wait()
|
||||
|
||||
hits, misses := c.Stats()
|
||||
if hits+misses != 5000 {
|
||||
t.Errorf("total calls = %d, want 5000", hits+misses)
|
||||
}
|
||||
// First call is a guaranteed miss; subsequent should mostly be
|
||||
// hits. With 50 concurrent goroutines hitting an empty cache,
|
||||
// up to ~50 first-arrivers may miss before the first one writes.
|
||||
if misses > 100 {
|
||||
t.Errorf("misses=%d unreasonably high; cache concurrency broken?", misses)
|
||||
}
|
||||
}
|
||||
|
||||
func TestCacheKey_StableAndDistinct(t *testing.T) {
|
||||
a := cacheKey("m1", "text-a")
|
||||
a2 := cacheKey("m1", "text-a")
|
||||
b := cacheKey("m1", "text-b")
|
||||
c := cacheKey("m2", "text-a")
|
||||
|
||||
if a != a2 {
|
||||
t.Errorf("cache key not stable: %q != %q", a, a2)
|
||||
}
|
||||
if a == b {
|
||||
t.Errorf("different texts produced same key: %q", a)
|
||||
}
|
||||
if a == c {
|
||||
t.Errorf("different models produced same key: %q", a)
|
||||
}
|
||||
// Key shape: model + ":" + 64-hex-chars sha256.
|
||||
const sha256HexLen = 64
|
||||
want := len("m1") + 1 + sha256HexLen
|
||||
if len(a) != want {
|
||||
t.Errorf("key len=%d, want %d", len(a), want)
|
||||
}
|
||||
}
|
||||
@ -65,11 +65,14 @@ type GatewayConfig struct {
|
||||
// EmbeddConfig drives the embed service. ProviderURL points at the
|
||||
// embedding backend (Ollama in G2, possibly OpenAI/Voyage in G3+).
|
||||
// DefaultModel is what gets used when callers don't specify a
|
||||
// model in their request body.
|
||||
// model in their request body. CacheSize is the LRU cache cap on
|
||||
// (model, sha256(text)) → vector lookups; 0 disables caching.
|
||||
// Default 10000 entries ≈ 30 MiB at d=768.
|
||||
type EmbeddConfig struct {
|
||||
Bind string `toml:"bind"`
|
||||
ProviderURL string `toml:"provider_url"`
|
||||
DefaultModel string `toml:"default_model"`
|
||||
CacheSize int `toml:"cache_size"`
|
||||
}
|
||||
|
||||
// VectordConfig adds vectord-specific knobs. StoragedURL is
|
||||
@ -153,6 +156,7 @@ func DefaultConfig() Config {
|
||||
Bind: "127.0.0.1:3216",
|
||||
ProviderURL: "http://localhost:11434", // local Ollama
|
||||
DefaultModel: "nomic-embed-text",
|
||||
CacheSize: 10_000, // ~30 MiB at d=768; set to 0 to disable
|
||||
},
|
||||
Queryd: QuerydConfig{
|
||||
Bind: "127.0.0.1:3214",
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user