From 2f31a570234a17928dc70ff01ecb257f1e6e3f5c Mon Sep 17 00:00:00 2001
From: Tim Vaillancourt <tim@timvaillancourt.com>
Date: Sat, 14 Dec 2024 23:43:34 +0100
Subject: [PATCH] remove unused `concurrency` field from topo watcher

Signed-off-by: Tim Vaillancourt <tim@timvaillancourt.com>
---
 go/vt/discovery/healthcheck.go           |  2 +-
 go/vt/discovery/topology_watcher.go      |  4 +---
 go/vt/discovery/topology_watcher_test.go | 10 +++++-----
 3 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/go/vt/discovery/healthcheck.go b/go/vt/discovery/healthcheck.go
index 0bd1d32c6bc..2f270bd7518 100644
--- a/go/vt/discovery/healthcheck.go
+++ b/go/vt/discovery/healthcheck.go
@@ -373,7 +373,7 @@ func NewHealthCheck(ctx context.Context, retryDelay, healthCheckTimeout time.Dur
 		if c == "" {
 			continue
 		}
-		topoWatchers = append(topoWatchers, NewTopologyWatcher(ctx, topoServer, hc, filters, c, refreshInterval, refreshKnownTablets, topo.DefaultReadConcurrency))
+		topoWatchers = append(topoWatchers, NewTopologyWatcher(ctx, topoServer, hc, filters, c, refreshInterval, refreshKnownTablets))
 	}
 
 	hc.topoWatchers = topoWatchers
diff --git a/go/vt/discovery/topology_watcher.go b/go/vt/discovery/topology_watcher.go
index 6581149f520..d1e358e1aa5 100644
--- a/go/vt/discovery/topology_watcher.go
+++ b/go/vt/discovery/topology_watcher.go
@@ -67,7 +67,6 @@ type TopologyWatcher struct {
 	cell                string
 	refreshInterval     time.Duration
 	refreshKnownTablets bool
-	concurrency         int64
 	ctx                 context.Context
 	cancelFunc          context.CancelFunc
 	// wg keeps track of all launched Go routines.
@@ -89,7 +88,7 @@ type TopologyWatcher struct {
 
 // NewTopologyWatcher returns a TopologyWatcher that monitors all
 // the tablets in a cell, and reloads them as needed.
-func NewTopologyWatcher(ctx context.Context, topoServer *topo.Server, hc HealthCheck, f TabletFilter, cell string, refreshInterval time.Duration, refreshKnownTablets bool, topoReadConcurrency int64) *TopologyWatcher {
+func NewTopologyWatcher(ctx context.Context, topoServer *topo.Server, hc HealthCheck, f TabletFilter, cell string, refreshInterval time.Duration, refreshKnownTablets bool) *TopologyWatcher {
 	tw := &TopologyWatcher{
 		topoServer:          topoServer,
 		healthcheck:         hc,
@@ -97,7 +96,6 @@ func NewTopologyWatcher(ctx context.Context, topoServer *topo.Server, hc HealthC
 		cell:                cell,
 		refreshInterval:     refreshInterval,
 		refreshKnownTablets: refreshKnownTablets,
-		concurrency:         topoReadConcurrency,
 		tablets:             make(map[string]*tabletInfo),
 	}
 	tw.firstLoadChan = make(chan struct{})
diff --git a/go/vt/discovery/topology_watcher_test.go b/go/vt/discovery/topology_watcher_test.go
index cef367c9b74..89a656c0982 100644
--- a/go/vt/discovery/topology_watcher_test.go
+++ b/go/vt/discovery/topology_watcher_test.go
@@ -67,7 +67,7 @@ func TestStartAndCloseTopoWatcher(t *testing.T) {
 	fhc := NewFakeHealthCheck(nil)
 	defer fhc.Close()
 	topologyWatcherOperations.ZeroAll()
-	tw := NewTopologyWatcher(context.Background(), ts, fhc, nil, "aa", 100*time.Microsecond, true, 5)
+	tw := NewTopologyWatcher(context.Background(), ts, fhc, nil, "aa", 100*time.Microsecond, true)
 
 	done := make(chan bool, 3)
 	result := make(chan bool, 1)
@@ -127,7 +127,7 @@ func checkWatcher(t *testing.T, refreshKnownTablets bool) {
 	logger := logutil.NewMemoryLogger()
 	topologyWatcherOperations.ZeroAll()
 	counts := topologyWatcherOperations.Counts()
-	tw := NewTopologyWatcher(context.Background(), ts, fhc, filter, "aa", 10*time.Minute, refreshKnownTablets, 5)
+	tw := NewTopologyWatcher(context.Background(), ts, fhc, filter, "aa", 10*time.Minute, refreshKnownTablets)
 
 	counts = checkOpCounts(t, counts, map[string]int64{})
 	checkChecksum(t, tw, 0)
@@ -421,7 +421,7 @@ func TestFilterByKeyspace(t *testing.T) {
 	f := TabletFilters{NewFilterByKeyspace(testKeyspacesToWatch)}
 	ts := memorytopo.NewServer(ctx, testCell)
 	defer ts.Close()
-	tw := NewTopologyWatcher(context.Background(), ts, hc, f, testCell, 10*time.Minute, true, 5)
+	tw := NewTopologyWatcher(context.Background(), ts, hc, f, testCell, 10*time.Minute, true)
 
 	for _, test := range testFilterByKeyspace {
 		// Add a new tablet to the topology.
@@ -502,7 +502,7 @@ func TestFilterByKeyspaceSkipsIgnoredTablets(t *testing.T) {
 	topologyWatcherOperations.ZeroAll()
 	counts := topologyWatcherOperations.Counts()
 	f := TabletFilters{NewFilterByKeyspace(testKeyspacesToWatch)}
-	tw := NewTopologyWatcher(context.Background(), ts, fhc, f, "aa", 10*time.Minute, false /*refreshKnownTablets*/, 5)
+	tw := NewTopologyWatcher(context.Background(), ts, fhc, f, "aa", 10*time.Minute, false /*refreshKnownTablets*/)
 
 	counts = checkOpCounts(t, counts, map[string]int64{})
 	checkChecksum(t, tw, 0)
@@ -639,7 +639,7 @@ func TestGetTabletErrorDoesNotRemoveFromHealthcheck(t *testing.T) {
 	defer fhc.Close()
 	topologyWatcherOperations.ZeroAll()
 	counts := topologyWatcherOperations.Counts()
-	tw := NewTopologyWatcher(context.Background(), ts, fhc, nil, "aa", 10*time.Minute, true, 5)
+	tw := NewTopologyWatcher(context.Background(), ts, fhc, nil, "aa", 10*time.Minute, true)
 	defer tw.Stop()
 
 	// Force fallback to getting tablets individually.