USB 2.0 bottleneck?

[idata]

Hi all,

In my current configuration I'm using a raspberry pi 3 with the movidius ncs. Based on this article:

https://movidius.github.io/blog/ncs-rpi3-mobilenets/It's possible to get >15FPS with a network with a size of 224_224. Now I'm using MobilenetSSD caffe implementation from NCS Appzoo folder and I can only get ~5FPS. Based on profiling data it could be much more faster. The network size in case of MobilenetSSD is 300_300, which results 300_300_3*16 bit = 4320000 bit = 540kB per frame, which is ~2.5MB/s in case of 5FPS. What do you think guys, is it possible that the USB 2.0 might be the bottleneck?Best,David

[idata]

Well it is simple math in my opinion. Raspbery pi shares EVERYTHING on one bus. This means the ONE usb 2.0 bus(which is split to 4 usb 2.0 ports) and the 100Gb/s ethernet port. If you are only using the usb bus for one thing, or the ethernet port without the usb ports, it will be around 11MB/s. But example if you download/upload with 5MB/s, you only have left 5-6MB/s for the usb2 port. I don't know your concept, but if you get your feed from the network, it sucks bandwidth from usb. And these are real numbers, because i download to my pi all the time at 11MB/s and copy files with average 10-13MB/s as well. Hope it helps.

[idata]

Sorry it is 100Mb/s, but I think you realized it :)