Writing performance is unstable.. Why? (reupload images)

Reading Performance from MC is perfect like this…

 

But Writing performance is surely unstable… (below 3pics)

 

All of test is 2,5GB large file sequencial test (samba).

It’s normal, reading is faster and consistent than writing to a harddisk. When you read, some info is already cached. But when you write the buffers gets filled up with new data very quickly thus need to flush regularly. 

Btw your write is quite good.