Write speed of eMMC Memory so slow !!!

Charlie Nguyen
Dear anyone,
 I'm coding a little tool to benchmark network.
 Everything have been fine, except the write speed of eMMC Memory of
NanoPC-T2 was lower than bandwidth of my network.
 I'm trying some benchmark tool and result that I was get just over 6~7MB/s
for write speed. Although at some website shown eMMC memory write speed
over 50 ~ 150MB/s.
 Anyone can help me solve this problem?