Why download speed from MBL is much slower than others?

I actually tested couple of times on each box, all gave consistent results, ~22MB/s on Mini, and 5-6MB/s on MBL.

I then plug MBL’s network cable to my laptop, I was able to get 27MB/s by single browser download instance, so cable has no issue.

I thought very high speed might be limited by MBL’s disk read/write speed, so I tried to download from another slow URL, didn’t save the result but it’s about ~50KB/s on MBL, and ~300KB/s on Mini, still huge difference.

A bit lost…

MBL is almost 90% full,  Media Server is off so no backend indexing process.