GODT-2085: Ensure minimum sync worker count

Make sure that we are at least using 16 workers for sync, otherwise
multiply the current sync worker count by 2.

Finally, this patch also logs the duration of the time it takes to
transfer all the messages from the server.

internal/vault/settings_test.go

@@ -18,7 +18,6 @@
 package vault_test
 
 import (
-	"runtime"
 	"testing"
 
 	"github.com/Masterminds/semver/v3"
@@ -222,6 +221,7 @@ func TestVault_Settings_SyncWorkers(t *testing.T) {
 	// create a new test vault.
 	s := newVault(t)
 
-	require.Equal(t, runtime.NumCPU(), s.SyncWorkers())
-	require.Equal(t, runtime.NumCPU(), s.SyncAttPool())
+	syncWorkers := vault.GetDefaultSyncWorkerCount()
+	require.Equal(t, syncWorkers, s.SyncWorkers())
+	require.Equal(t, syncWorkers, s.SyncAttPool())
 }

internal/vault/types_settings.go

@@ -49,7 +49,21 @@ type Settings struct {
 	SyncAttPool int
 }
 
+func GetDefaultSyncWorkerCount() int {
+	const minSyncWorkers = 16
+
+	syncWorkers := runtime.NumCPU() * 2
+
+	if syncWorkers < minSyncWorkers {
+		syncWorkers = minSyncWorkers
+	}
+
+	return syncWorkers
+}
+
 func newDefaultSettings(gluonDir string) Settings {
+	syncWorkers := GetDefaultSyncWorkerCount()
+
 	return Settings{
 		GluonDir: gluonDir,
 
@@ -71,7 +85,7 @@ func newDefaultSettings(gluonDir string) Settings {
 		FirstStart:    true,
 		FirstStartGUI: true,
 
-		SyncWorkers: runtime.NumCPU(),
-		SyncAttPool: runtime.NumCPU(),
+		SyncWorkers: syncWorkers,
+		SyncAttPool: syncWorkers,
 	}
 }