Slow Chunk Generation

So after this recent update ive bin running into a problem involving chunks not generating.  Ill walk around an see chunks in the map not showing.  Not sure what could cause this,  Ill leave some images showing what I mean.  If there is any way I can help resolve this, ill be glad to do so.  Ive tried to find a solution to this but have came up short.  Even when looking through these posts.