By default your MTU is 1500. Here is how you increase it to 9000 to enable Jumbo Frames, with no network impact. It will speed up your system because it does not have to repeatedly send the header info on every small packet.
Login into your Synology
Go to Control Panel
Select Network
Then go to Network Interface
Select Lan 1
Then press Edit
Checkmark MTU and set the value to 9000
Click Ok
Click Yes
Then do the same for Lan 2
Thats it. You now have jumbo frames