Ejemplo n.º 1
0
// This method never blocks. It'll buffer writes until they fill the buffer then drop the on the
// floor and let the background goroutine replay from the WAL
func (self *WriteBuffer) Write(request *protocol.Request) {
	self.shardLastRequestNumber[request.GetShardId()] = request.GetRequestNumber()
	select {
	case self.writes <- request:
		log.Debug("Buffering %d:%d for %s", request.GetRequestNumber(), request.GetShardId(), self.writerInfo)
		return
	default:
		select {
		case self.stoppedWrites <- *request.RequestNumber:
			return
		default:
			return
		}
	}
}
Ejemplo n.º 2
0
func (self *WriteBuffer) write(request *protocol.Request) {
	attempts := 0
	for {
		self.shardIds[*request.ShardId] = true
		err := self.writer.Write(request)
		if err == nil {
			requestNumber := request.RequestNumber
			if requestNumber == nil {
				return
			}

			self.shardCommitedRequestNumber[request.GetShardId()] = *requestNumber
			log.Debug("Commiting %d:%d for %s", request.GetRequestNumber(), request.GetShardId(), self.writerInfo)
			self.wal.Commit(*requestNumber, self.serverId)
			return
		}
		if attempts%100 == 0 {
			log.Error("%s: WriteBuffer: error on write to server %d: %s", self.writerInfo, self.serverId, err)
		}
		attempts += 1
		// backoff happens in the writer, just sleep for a small fixed amount of time before retrying
		time.Sleep(time.Millisecond * 100)
	}
}