Merge pull request #1475 from levenlabs/lock

Fix deadlock with KeepConnected and SendHeartbeat
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Chris Lu 2020-09-21 19:49:15 -07:00 committed by GitHub
commit ec5b9f1e91
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2 changed files with 9 additions and 3 deletions

View file

@ -99,7 +99,7 @@ func init() {
serverOptions.v.fileSizeLimitMB = cmdServer.Flag.Int("volume.fileSizeLimitMB", 1024, "limit file size to avoid out of memory")
serverOptions.v.publicUrl = cmdServer.Flag.String("volume.publicUrl", "", "publicly accessible address")
serverOptions.v.preStopSeconds = cmdServer.Flag.Int("volume.preStopSeconds", 10, "number of seconds between stop send heartbeats and stop volume server")
serverOptions.v.pprof = &False
serverOptions.v.pprof = cmdServer.Flag.Bool("volume.pprof", false, "enable pprof http handlers. precludes --memprofile and --cpuprofile")
s3Options.port = cmdServer.Flag.Int("s3.port", 8333, "s3 server http listen port")
s3Options.domainName = cmdServer.Flag.String("s3.domainName", "", "suffix of the host name, {bucket}.{domainName}")

View file

@ -187,7 +187,8 @@ func (ms *MasterServer) KeepConnected(stream master_pb.Seaweed_KeepConnectedServ
peerAddress := findClientAddress(stream.Context(), req.GrpcPort)
stopChan := make(chan bool)
// buffer by 1 so we don't end up getting stuck writing to stopChan forever
stopChan := make(chan bool, 1)
clientName, messageChan := ms.addClient(req.Name, peerAddress)
@ -247,7 +248,12 @@ func (ms *MasterServer) addClient(clientType string, clientAddress string) (clie
clientName = clientType + "@" + clientAddress
glog.V(0).Infof("+ client %v", clientName)
messageChan = make(chan *master_pb.VolumeLocation)
// we buffer this because otherwise we end up in a potential deadlock where
// the KeepConnected loop is no longer listening on this channel but we're
// trying to send to it in SendHeartbeat and so we can't lock the
// clientChansLock to remove the channel and we're stuck writing to it
// 100 is probably overkill
messageChan = make(chan *master_pb.VolumeLocation, 100)
ms.clientChansLock.Lock()
ms.clientChans[clientName] = messageChan