StackExchange.Redis - 等待锁定的最佳方式

I have the following method that waits for an exclusive lock on a Redis key. This method works but I'm wondering if there is a better way without a for loop and a Thread.Sleep.

我有以下方法等待Redis密钥的独占锁。这种方法有效,但我想知道没有for循环和Thread.Sleep是否有更好的方法。

    /// <summary>
    /// wait up to 2 seconds to achieve a lock!  
    /// The lock is good for a maximum of 3 seconds
    /// </summary>
    /// <param name="codeID"></param>
    internal void WaitForSingleUseLock(CodeID codeID)
    {
        var key = _redemptionRepo.SingleUseCodeLockPrefix + codeID.Value;
        var expiration = TimeSpan.FromSeconds(3);
        for (var i = 0; i < 20; i++)
        {
            var lockAchieved = _cacheRepo.LockTake(key, "1", expiration);
            if (lockAchieved)
            {
                break;
            }
            Thread.Sleep(TimeSpan.FromMilliseconds(100));
        }
    }

2 个解决方案

#1

The only thing I could suggest different would be to consider pub/sub as a side channel (meaning: in addition, not replacement) for indicating when the lock might now be available - i.e. publish when releasing, and use the sub to release a timer (via a monitor or an async-wait-handle).

我唯一可以建议不同的是将pub / sub视为侧面通道(意思是:此外,不是替换),用于指示锁定现在何时可用 - 即释放时发布,并使用sub释放计时器(通过监视器或异步等待句柄)。

Other than that: nope. Redis doesn't have the idea of a pending queue. You could perhaps possibly construct one using lists, but...

除此之外:不。 Redis没有挂起队列的想法。您也许可以使用列表构建一个,但是......

#2

After taking @Marc's comments into consideration and meeting with my team about the benefits of Task.Delay() over Thread.Sleep() in this context I decided on this as a final solution:

在考虑了@ Marc的评论并与我的团队讨论了在此上下文中Task.Delay()对Thread.Sleep()的好处之后,我决定将其作为最终解决方案:

    /// <summary>
    /// wait up to 3 seconds to achieve a lock!  
    /// The lock is good for a maximum of 3 seconds
    /// 
    /// Returns the total amount of time until the lock was taken
    /// </summary>
    internal virtual async Task<TimeSpan> WaitForSingleUseLock(CodeID codeID)
    {
        var key = _redemptionRepo.SingleUseCodeLockPrefix + codeID.Value;
        var totalTime = TimeSpan.Zero;
        var maxTime = TimeSpan.FromSeconds(3);
        var expiration = TimeSpan.FromSeconds(3);
        var sleepTime = TimeSpan.FromMilliseconds(50);
        var lockAchieved = false;

        while (!lockAchieved && totalTime < maxTime)
        {
            lockAchieved = _cacheRepo.LockTake(key, "1", expiration);
            if (lockAchieved)
            {
                continue;
            }
            await Task.Delay(sleepTime);
            totalTime += sleepTime;
        }
        return totalTime;
    }

#1