Hi, abit! Thanks a lot for your reply! I'm now have better understanding of bitshares working process.
And now i have some more questions, maybe simple, but interesting:

 How bitshares will work in this situation: Bob put his order to buy 10 bitUSD for 1.7 BTS, then Alice and Dan, simultaneously put their orders to sell 10 bitUSD for 1.7.  Alice and Dan using two different nodes(witnesses) to put orders to the network. What will happen? Which order will be chosen to fill Bobs order and why?
How will Alice and Dan orders be processed through transactions chain? Who decide which order will fill if they created orders absolutely simultaneously ?

 

Hi, All
Can anybody explain in more technical details how the DEX matching works?
I search through the code and found graphene::chain::database::apply_order(...) function which then call to fill_order() function and so on... But i do not understand how DEX is actually change user balances after orders matching (i mean, i do not understand how the blockchain is working here ).