基于Orleans的分布式Id生成方案，因Orleans的单实例、单线程模型，让这种实现变的简单,贴出一种实现，欢迎大家提出意见
public interface ISequenceNoGenerator : Orleans.IGrainWithIntegerKey
{
Task<Immutable<string>> GetNext();
}
public class SequenceNoGenerator : Orleans.Grain, ISequenceNoGenerator
{
private const int MaxSeed = ;
private int _seed = ;
private int _currentSecondCounter = ;
Task<Immutable<string>> ISequenceNoGenerator.GetNext()
{
var oldCounter = this._currentSecondCounter; while (true)
{
this.UpdateCurrentTimestamp(); if (oldCounter != this._currentSecondCounter)
this._seed = ;
else
{
++this._seed;
} if (this._seed > MaxSeed) Task.Delay();
else break;
} var seq = DateTime.Now.ToString("yyyyMMdd") + this._currentSecondCounter.ToString() + this._seed.ToString();
return Task.FromResult(seq.AsImmutable());
} public override Task OnActivateAsync()
{
//延迟1秒启动，防止Activation在某个机器上崩溃后，在集群中其它host上启动时，sequenceNo在同一秒出现重复
Task.Delay(); return base.OnActivateAsync();
} private void UpdateCurrentTimestamp()
{
var currentTime = DateTime.Now;
var currentDayStart = Convert.ToDateTime(currentTime.ToShortDateString());
this._currentSecondCounter = (int)(new TimeSpan(currentTime.Ticks - currentDayStart.Ticks).TotalSeconds);
}
}