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。