Pi W webcamd stopped - still stutters


#1

I know web streaming on the Pi W under OctoPi is a no-no. So I disabled the webcamd via crontab at boot and verified that it was indeed disabled via SSH into OctoPi:
service webcamd status
and it is showing that its not started:

ā— webcamd.service - LSB: webcam daemon
   Loaded: loaded (/etc/init.d/webcamd; generated; vendor preset: enabled)
   Active: inactive (dead) since Tue 2018-08-14 21:54:19 CST; 34min ago
     Docs: man:systemd-sysv-generator(8)
  Process: 466 ExecStop=/etc/init.d/webcamd stop (code=exited, status=0/SUCCESS)
  Process: 407 ExecStart=/etc/init.d/webcamd start (code=exited, status=0/SUCCES

Aug 14 21:54:19 Kossel systemd[1]: Starting LSB: webcam daemon...
Aug 14 21:54:19 Kossel webcamd[407]: Starting Webcam Daemon: webcamd.
Aug 14 21:54:19 Kossel systemd[1]: Started LSB: webcam daemon.
Aug 14 21:54:19 Kossel systemd[1]: Stopping LSB: webcam daemon...
Aug 14 21:54:19 Kossel webcamd[466]: Stopping Webcam Daemon: webcamd.
Aug 14 21:54:19 Kossel systemd[1]: Stopped LSB: webcam daemon.

Yet, prints still stutter under the Pi W. And I even closed the OctoPi Web page, and it still stutters.

I popped the SD card out of the Pi W and put it in the Pi 3B+ and stuttering disappeared, of course (exact same gCode file)

This is on an AnyCubic Kossel Delta 3D Printer running Marlin 1.1.9
Latest version of OctoPrint v1.3.9
OctoPi version 0.15.1
I'm printing at 40mm/s
USB Baud Rate is 250000

Am I missing something or is the Pi W just not even fast enough to send G-code commands to the printer - period??

Thanks!!


#2

It heavily depends on the GCODE you are sending - lots of curves = more throughput = CPU becomes a bottle neck faster.

I strongly recommend against using the Pi Zero W not only if you want to use a webcam - this things is simply ill suited thanks to a single core, a wifi interface that hogs what little CPU is available once any kind of traffic is generated through whatever means and all that hassle if you want to connect USB devices to it.


#3

Thanks for the quick response.
I was afraid of this - while still hoping there was enough horse-power in the Pi Zero to just send gCodes.
My whole motivation for going Zero was space - there is just not much inside that Delta printer. Looks like I'll have to hang a big wart off the side now :frowning:
Oh well, it was a learning experience.
Thanks again!


#4

Setup a stand-alone Raspberry Pi Zero W as your camera.


#5

Yup, Probably re-purpose it as a '3rd' time-lapse camera :slight_smile: