Biztalk FlatFile Disassembler Processing behavior

Recently I had a scenario which involves processing a large amount of flat files; each of whihc went througha Flatfile Dissasembler before the business processing on that started. Here I record some points of interest of FFDASM behaviour. When FlatFile Disassembler is fed with a large amount of files biztalk waits for all files to unpack before it starts processing.

Our test environment had two boxes each both of which configured under the same host and having identical machine config with SQL on a seperate box was used for the test
For our Scenario we had little over 500 files being dropped simultaneously .The file batch size was set at 20 the default.. It was noticed that after picking up the first 20 and initiating disassembling this batch before the next set is picked up , it goes on picks up all the files.( See graph)

Essentially Biztalk seemed to wait for all the messages to get picked up and then flat file disassembler unpacks all of the flat files from the interchange before it starts processing. This is evident from the apparent lack of activity form the time the last file was picked up and when the first set of files started coming out ( See Graph) . I had seen this in one of prior instance and I recently ran some test and got similar results which made me write this post.



Biztalk Flat File Dissasembler Behaviour