Understanding code/closure shipment to Spark workers‏

[Arijit]

 Hi,
 
I want to understand the code flow starting from the Spark jar that I submit 
through spark-submit, how does Spark identify and extract the closures, clean 
and serialize them and ship them to workers to execute as tasks. Can someone 
point me to any documentation or a pointer to the source code path to help me 
understand this.
 
Thanks, Arijit