title: Multi-threading in custom SSIS transformation data flow task
body: <p>I have an SSIS package which does this:
  1. Read records from flat file source
  2. Transform by calling webservice which adds additional response column to buffer
  3. Output all input records and response column into destination file.</p>
  
  <p>2 is a custom transformation data flow task I wrote, which is synchronous because I am outputting the input.</p>
  
  <p>I initially thought from the default buffersizes and engineThread properties that it was multithreaded already and would call multiple ProcessInputs at the same time. But once I ran it, realised that it only called the web service one at a time.</p>
  
  <p>How can I make it multi-threaded?
  I've googled around but found myself getting more confused.</p>
  
  <p>Thanks in advance</p>