Whenever I go to the nether long strips of chunks are missing, I tested this in single player and multiplayer and it happened in both scenarios.
What I expected to happen was the Nether to load properly, but instead every other chunk wouldn't load in very long (seemed infinite) strips .

Steps to Reproduce:
1. Build any size nether portal
2. Light the nether portal using flint and steel in players hand.
3. Walk into the nether portal and once in the nether, look around.