Added user sharding to WsHubImpl to help reduce the amount of lock contention in the upcoming features which will rely heavily on it.

This commit is contained in:
Azareal 2018-07-18 16:32:48 +10:00
parent 101d4522fa
commit e5ef86b59c
1 changed files with 111 additions and 46 deletions

View File

@ -31,11 +31,15 @@ type WSUser struct {
// TODO: Make this an interface? // TODO: Make this an interface?
type WsHubImpl struct { type WsHubImpl struct {
// TODO: Shard this map // TODO: Implement some form of generics so we don't write as much odd-even sharding code
OnlineUsers map[int]*WSUser evenOnlineUsers map[int]*WSUser
oddOnlineUsers map[int]*WSUser
evenUserLock sync.RWMutex
oddUserLock sync.RWMutex
// TODO: Add sharding for this too?
OnlineGuests map[*WSUser]bool OnlineGuests map[*WSUser]bool
GuestLock sync.RWMutex GuestLock sync.RWMutex
UserLock sync.RWMutex
lastTick time.Time lastTick time.Time
lastTopicList []*TopicsRow lastTopicList []*TopicsRow
@ -54,8 +58,9 @@ func init() {
topicListWatchers = make(map[*WSUser]bool) topicListWatchers = make(map[*WSUser]bool)
// TODO: Do we really want to initialise this here instead of in main.go / general_test.go like the other things? // TODO: Do we really want to initialise this here instead of in main.go / general_test.go like the other things?
WsHub = WsHubImpl{ WsHub = WsHubImpl{
OnlineUsers: make(map[int]*WSUser), evenOnlineUsers: make(map[int]*WSUser),
OnlineGuests: make(map[*WSUser]bool), oddOnlineUsers: make(map[int]*WSUser),
OnlineGuests: make(map[*WSUser]bool),
} }
} }
@ -222,32 +227,107 @@ func (hub *WsHubImpl) GuestCount() int {
return len(hub.OnlineGuests) return len(hub.OnlineGuests)
} }
func (hub *WsHubImpl) UserCount() int { func (hub *WsHubImpl) UserCount() (count int) {
defer hub.UserLock.RUnlock() hub.evenUserLock.RLock()
hub.UserLock.RLock() count += len(hub.evenOnlineUsers)
return len(hub.OnlineUsers) hub.evenUserLock.RUnlock()
hub.oddUserLock.RLock()
count += len(hub.oddOnlineUsers)
hub.oddUserLock.RUnlock()
return count
} }
func (hub *WsHubImpl) broadcastMessage(msg string) error { func (hub *WsHubImpl) broadcastMessage(msg string) error {
hub.UserLock.RLock() var userLoop = func(users map[int]*WSUser, mutex *sync.RWMutex) error {
defer hub.UserLock.RUnlock() defer mutex.RUnlock()
for _, wsUser := range hub.OnlineUsers { for _, wsUser := range users {
w, err := wsUser.conn.NextWriter(websocket.TextMessage) w, err := wsUser.conn.NextWriter(websocket.TextMessage)
if err != nil { if err != nil {
return err return err
}
_, _ = w.Write([]byte(msg))
w.Close()
} }
_, _ = w.Write([]byte(msg)) return nil
w.Close() }
// TODO: Can we move this RLock inside the closure safely?
hub.evenUserLock.RLock()
err := userLoop(hub.evenOnlineUsers, &hub.evenUserLock)
if err != nil {
return err
}
hub.oddUserLock.RLock()
return userLoop(hub.oddOnlineUsers, &hub.oddUserLock)
}
func (hub *WsHubImpl) getUser(uid int) (wsUser *WSUser, err error) {
var ok bool
if uid%2 == 0 {
hub.evenUserLock.RLock()
wsUser, ok = hub.evenOnlineUsers[uid]
hub.evenUserLock.RUnlock()
} else {
hub.oddUserLock.RLock()
wsUser, ok = hub.oddOnlineUsers[uid]
hub.oddUserLock.RUnlock()
}
if !ok {
return nil, errWsNouser
}
return wsUser, nil
}
// Warning: For efficiency, some of the *WSUsers may be nil pointers, DO NOT EXPORT
func (hub *WsHubImpl) getUsers(uids []int) (wsUsers []*WSUser, err error) {
if len(uids) == 0 {
return nil, errWsNouser
}
hub.evenUserLock.RLock()
// We don't want to keep a lock on this for too long, so we'll accept some nil pointers
for _, uid := range uids {
wsUsers = append(wsUsers, hub.evenOnlineUsers[uid])
}
hub.evenUserLock.RUnlock()
hub.oddUserLock.RLock()
// We don't want to keep a lock on this for too long, so we'll accept some nil pointers
for _, uid := range uids {
wsUsers = append(wsUsers, hub.oddOnlineUsers[uid])
}
hub.oddUserLock.RUnlock()
if len(wsUsers) == 0 {
return nil, errWsNouser
}
return wsUsers, nil
}
func (hub *WsHubImpl) SetUser(uid int, wsUser *WSUser) {
if uid%2 == 0 {
hub.evenUserLock.Lock()
hub.evenOnlineUsers[uid] = wsUser
hub.evenUserLock.Unlock()
} else {
hub.oddUserLock.Lock()
hub.oddOnlineUsers[uid] = wsUser
hub.oddUserLock.Unlock()
}
}
func (hub *WsHubImpl) RemoveUser(uid int) {
if uid%2 == 0 {
hub.evenUserLock.Lock()
delete(hub.evenOnlineUsers, uid)
hub.evenUserLock.Unlock()
} else {
hub.oddUserLock.Lock()
delete(hub.oddOnlineUsers, uid)
hub.oddUserLock.Unlock()
} }
return nil
} }
func (hub *WsHubImpl) pushMessage(targetUser int, msg string) error { func (hub *WsHubImpl) pushMessage(targetUser int, msg string) error {
hub.UserLock.RLock() wsUser, err := hub.getUser(targetUser)
wsUser, ok := hub.OnlineUsers[targetUser] if err != nil {
hub.UserLock.RUnlock() return err
if !ok {
return errWsNouser
} }
w, err := wsUser.conn.NextWriter(websocket.TextMessage) w, err := wsUser.conn.NextWriter(websocket.TextMessage)
@ -261,21 +341,16 @@ func (hub *WsHubImpl) pushMessage(targetUser int, msg string) error {
} }
func (hub *WsHubImpl) pushAlert(targetUser int, asid int, event string, elementType string, actorID int, targetUserID int, elementID int) error { func (hub *WsHubImpl) pushAlert(targetUser int, asid int, event string, elementType string, actorID int, targetUserID int, elementID int) error {
//log.Print("In pushAlert") wsUser, err := hub.getUser(targetUser)
hub.UserLock.RLock() if err != nil {
wsUser, ok := hub.OnlineUsers[targetUser] return err
hub.UserLock.RUnlock()
if !ok {
return errWsNouser
} }
//log.Print("Building alert")
alert, err := BuildAlert(asid, event, elementType, actorID, targetUserID, elementID, *wsUser.User) alert, err := BuildAlert(asid, event, elementType, actorID, targetUserID, elementID, *wsUser.User)
if err != nil { if err != nil {
return err return err
} }
//log.Print("Getting WS Writer")
w, err := wsUser.conn.NextWriter(websocket.TextMessage) w, err := wsUser.conn.NextWriter(websocket.TextMessage)
if err != nil { if err != nil {
return err return err
@ -287,15 +362,9 @@ func (hub *WsHubImpl) pushAlert(targetUser int, asid int, event string, elementT
} }
func (hub *WsHubImpl) pushAlerts(users []int, asid int, event string, elementType string, actorID int, targetUserID int, elementID int) error { func (hub *WsHubImpl) pushAlerts(users []int, asid int, event string, elementType string, actorID int, targetUserID int, elementID int) error {
var wsUsers []*WSUser wsUsers, err := hub.getUsers(users)
hub.UserLock.RLock() if err != nil {
// We don't want to keep a lock on this for too long, so we'll accept some nil pointers return err
for _, uid := range users {
wsUsers = append(wsUsers, hub.OnlineUsers[uid])
}
hub.UserLock.RUnlock()
if len(wsUsers) == 0 {
return errWsNouser
} }
var errs []error var errs []error
@ -344,9 +413,7 @@ func RouteWebsockets(w http.ResponseWriter, r *http.Request, user User) RouteErr
WsHub.OnlineGuests[wsUser] = true WsHub.OnlineGuests[wsUser] = true
WsHub.GuestLock.Unlock() WsHub.GuestLock.Unlock()
} else { } else {
WsHub.UserLock.Lock() WsHub.SetUser(user.ID, wsUser)
WsHub.OnlineUsers[user.ID] = wsUser
WsHub.UserLock.Unlock()
} }
//conn.SetReadLimit(/* put the max request size from earlier here? */) //conn.SetReadLimit(/* put the max request size from earlier here? */)
@ -361,9 +428,7 @@ func RouteWebsockets(w http.ResponseWriter, r *http.Request, user User) RouteErr
WsHub.GuestLock.Unlock() WsHub.GuestLock.Unlock()
} else { } else {
// TODO: Make sure the admin is removed from the admin stats list in the case that an error happens // TODO: Make sure the admin is removed from the admin stats list in the case that an error happens
WsHub.UserLock.Lock() WsHub.RemoveUser(user.ID)
delete(WsHub.OnlineUsers, user.ID)
WsHub.UserLock.Unlock()
} }
break break
} }