From 4a9240c2a3ac209f8e94548b7ad27eab8c25c5e9 Mon Sep 17 00:00:00 2001
From: Jeremy <acm_123@163.com>
Date: Mon, 7 Aug 2023 11:22:33 +0800
Subject: [PATCH] bit operation

Signed-off-by: Jeremy <acm_123@163.com>
---
 server/etcdserver/api/v2store/event_queue.go |  6 +++---
 server/etcdserver/api/v2store/event_test.go  | 11 +++++------
 server/etcdserver/api/v2store/store.go       |  2 +-
 3 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/server/etcdserver/api/v2store/event_queue.go b/server/etcdserver/api/v2store/event_queue.go
index 7ea03de8c9a..43117acbfa2 100644
--- a/server/etcdserver/api/v2store/event_queue.go
+++ b/server/etcdserver/api/v2store/event_queue.go
@@ -19,15 +19,15 @@ type eventQueue struct {
 	Size     int
 	Front    int
 	Back     int
-	Capacity int
+	Capacity int  // capacity must be 2^n
 }
 
 func (eq *eventQueue) insert(e *Event) {
 	eq.Events[eq.Back] = e
-	eq.Back = (eq.Back + 1) % eq.Capacity
+	eq.Back = (eq.Back + 1) & (eq.Capacity - 1)
 
 	if eq.Size == eq.Capacity { //dequeue
-		eq.Front = (eq.Front + 1) % eq.Capacity
+		eq.Front = (eq.Front + 1) & (eq.Capacity - 1)
 	} else {
 		eq.Size++
 	}
diff --git a/server/etcdserver/api/v2store/event_test.go b/server/etcdserver/api/v2store/event_test.go
index 6fc25fd74c9..00f07681523 100644
--- a/server/etcdserver/api/v2store/event_test.go
+++ b/server/etcdserver/api/v2store/event_test.go
@@ -25,7 +25,7 @@ import (
 // previous 100 events have been swapped out.
 func TestEventQueue(t *testing.T) {
 
-	eh := newEventHistory(100)
+	eh := newEventHistory(128)
 
 	// Add
 	for i := 0; i < 200; i++ {
@@ -48,7 +48,7 @@ func TestEventQueue(t *testing.T) {
 }
 
 func TestScanHistory(t *testing.T) {
-	eh := newEventHistory(100)
+	eh := newEventHistory(128)
 
 	// Add
 	eh.addEvent(newEvent(Create, "/foo", 1, 1))
@@ -91,17 +91,16 @@ func TestScanHistory(t *testing.T) {
 }
 
 func TestEventIndexHistoryCleared(t *testing.T) {
-	eh := newEventHistory(5)
+	eh := newEventHistory(4)
 
 	// Add
 	eh.addEvent(newEvent(Create, "/foo", 1, 1))
 	eh.addEvent(newEvent(Create, "/foo/bar", 2, 2))
 	eh.addEvent(newEvent(Create, "/foo/foo", 3, 3))
 	eh.addEvent(newEvent(Create, "/foo/bar/bar", 4, 4))
-	eh.addEvent(newEvent(Create, "/foo/foo/foo", 5, 5))
 
 	// Add a new event which will replace/de-queue the first entry
-	eh.addEvent(newEvent(Create, "/foo/bar/bar/bar", 6, 6))
+	eh.addEvent(newEvent(Create, "/foo/foo/foo", 5, 5))
 
 	// test for the event which has been replaced.
 	_, err := eh.scan("/foo", false, 1)
@@ -115,7 +114,7 @@ func TestEventIndexHistoryCleared(t *testing.T) {
 // works still for previous events.
 func TestFullEventQueue(t *testing.T) {
 
-	eh := newEventHistory(10)
+	eh := newEventHistory(8)
 
 	// Add
 	for i := 0; i < 1000; i++ {
diff --git a/server/etcdserver/api/v2store/store.go b/server/etcdserver/api/v2store/store.go
index 32cb26ad964..e5f46bc0ca7 100644
--- a/server/etcdserver/api/v2store/store.go
+++ b/server/etcdserver/api/v2store/store.go
@@ -98,7 +98,7 @@ func newStore(namespaces ...string) *store {
 		s.Root.Add(newDir(s, namespace, s.CurrentIndex, s.Root, Permanent))
 	}
 	s.Stats = newStats()
-	s.WatcherHub = newWatchHub(1000)
+	s.WatcherHub = newWatchHub(1024)
 	s.ttlKeyHeap = newTtlKeyHeap()
 	s.readonlySet = types.NewUnsafeSet(append(namespaces, "/")...)
 	return s