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  • SSIS 关于并发的两个设置

    1.MaxConcurrentExecutables(包级别的并发度控制)

    MaxConcurrentExecutables, a package level property in SSIS determines the number of control flow items that can be executed in parallel. The default value is -1. This is equivalent to number of processors (logical and physical) plus 2.

    For example, in the below package running on my machine with 4 processors and MaxConcurrentExecutables = -1, you can see 6 tasks have completed execution and 6 are currently running. It’s executing 6 at a time because 4 processors + 2 = 6 threads.

    This applies to all versions of SSIS. Parallelism is powerful when your goal is to complete a process as quickly as possible, specially when the tasks in a control flow are independent of each other.

    If you’re thinking of increasing this setting to an infinity hoping to achieve a Nobel prize in performance tuning… slow down. If the words throughput, threading, multi-tasking scares you, you should be careful with this property. In most cases, the default setting can get the job done just fine.

    2.EngineThreads(数据流任务中的并发度控制)

    EngineThreads 属性  这是数据流任务中的属性,它定义有多少个工作线程在引擎调度时可以被使用。缺省值为5,可设置范围为2-60之间,建议根据物理CPU个数调高到总CPU个数左右。如双核8CPU的服务器(CPU核心总数为16),可设置为15-17个左右,具体应依实际对比测试性能而定。
    注:多核处理器应当算作多个处理器。

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  • 原文地址:https://www.cnblogs.com/OpenCoder/p/5148831.html
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