[Postgres-xc-developers] Two questions about GTM

[normandi <nor...@al...>]

Hi all,
 When reading the Postgres-XC document, I got the following two questions (the same in nature  maybe :) )

 Q1: Why XC need the GTM component? 
   In my opinion,if a transaction is submitted at the coord node , the coord should break it
 up into a collection of subtransactions which will be submit to the corresponding data nodes,and the subtransaction will be resolved by datanode's local transaction manager.  Coordinator can decide whether commit the transaction or not ,by means of 2PC/3PC protocol.
 
 Q2: "same Timestamp view",  how it will affect the App clients?  What is means ? 
 
 

 Thanks a lot!

 Best Regards!