Move dedicated spawn token log to gRPC logs

Spawn token occasionally dumps some logs in two cases:
- The queuing time exceeds a certain threshold
- Fail to acquire the spawn token

Those logs are also dedicated logs outside of major gRPC logs. This
makes debugging and investigating a little bit hard. This commit moves
this kind of logs to gRPC logs. This change consolidates the logs in the
same place. It also removes redundant "spawn token acquired" logs.

2 files changed, 33 insertions, 10 deletions

diff --git a/internal/command/spawntoken.go b/internal/command/spawntoken.go
index b49a32192..bdc4d664c 100644
--- a/internal/command/spawntoken.go
+++ b/internal/command/spawntoken.go
@@ -5,15 +5,12 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/grpc-ecosystem/go-grpc-middleware/logging/logrus/ctxlogrus"
 	"github.com/kelseyhightower/envconfig"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
 	"gitlab.com/gitlab-org/gitaly/v16/internal/tracing"
 )
 
-const logDurationThreshold = 5 * time.Millisecond
-
 var (
 	spawnTokens chan struct{}
 	spawnConfig SpawnConfig
@@ -63,7 +60,7 @@ func getSpawnToken(ctx context.Context) (putToken func(), err error) {
 
 	select {
 	case spawnTokens <- struct{}{}:
-		logTime(ctx, start, "spawn token acquired")
+		logTime(ctx, start, "")
 
 		return func() {
 			<-spawnTokens
@@ -83,11 +80,8 @@ func logTime(ctx context.Context, start time.Time, msg string) {
 
 	if stats := StatsFromContext(ctx); stats != nil {
 		stats.RecordSum("command.spawn_token_wait_ms", int(delta.Milliseconds()))
+		if len(msg) != 0 {
+			stats.RecordMetadata("command.spawn_token_error", msg)
+		}
 	}
-
-	if delta < logDurationThreshold {
-		return
-	}
-
-	ctxlogrus.Extract(ctx).WithField("spawn_queue_ms", delta.Seconds()*1000).Info(msg)
 }
diff --git a/internal/command/spawntoken_test.go b/internal/command/spawntoken_test.go
index 014802fff..3f10d5bb3 100644
--- a/internal/command/spawntoken_test.go
+++ b/internal/command/spawntoken_test.go
@@ -8,6 +8,8 @@ import (
 )
 
 func TestGetSpawnToken_CommandStats(t *testing.T) {
+	t.Parallel()
+
 	ctx := testhelper.Context(t)
 	ctx = InitContextStats(ctx)
 
@@ -19,3 +21,30 @@ func TestGetSpawnToken_CommandStats(t *testing.T) {
 	require.NotNil(t, stats)
 	require.Contains(t, stats.Fields(), "command.spawn_token_wait_ms")
 }
+
+// This test modifies a global config, hence should never run in parallel
+func TestGetSpawnToken_CommandStats_timeout(t *testing.T) {
+	priorTimeout := spawnConfig.Timeout
+	priorSpawnTokens := spawnTokens
+
+	spawnConfig.Timeout = 0
+	spawnTokens = make(chan struct{}, 1)
+	spawnTokens <- struct{}{}
+	defer func() {
+		spawnConfig.Timeout = priorTimeout
+		spawnTokens = priorSpawnTokens
+	}()
+
+	ctx := testhelper.Context(t)
+	ctx = InitContextStats(ctx)
+
+	_, err := getSpawnToken(ctx)
+	require.ErrorContains(t, err, "process spawn timed out after")
+
+	stats := StatsFromContext(ctx)
+	require.NotNil(t, stats)
+	fields := stats.Fields()
+
+	require.GreaterOrEqual(t, fields["command.spawn_token_wait_ms"], 0)
+	require.Equal(t, fields["command.spawn_token_error"], "spawn token timeout")
+}