Large amounts of TNT placed crashes server. Did not blow up.

What I expected to happen was...:
The game runs normal while I approach the large amounts of blocks. 2 GB out of 8 GB of ram where actually being used ( source Windows task manager )
What actually happened was...:
As I approached the large amounts of blocks the game showed a screen of "SERVER CLOSED" and the window shut off.
Steps to Reproduce:
1. Place around 1000 blocks in a 8X8 chunk area.
2. Get a fair distance of the 1000 blocks.
3. Restart the game and rejoin the world, start approaching the blocks.
By the way, the first attachment is the place I spawned, the second is where the game lagged ( Still only 2 GB of ram used ) so I started spamming F2. It crashed then, the first 2 attempts where it crashed, I was not spamming F2. Please fix this.