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Comment: Migration of unmigrated content due to installation of a new plugin

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Code Block
apt-get install isc-dhcp-server

Slow SSH

With the gumstix in AP mode you may find ssh slow to provide a password prompt.  This is likely because DNS lookup is timing out without internet access / a DNS server available.  To disable reverse DNS lookup at the line "UseDNS no" to /etc/ssh/sshd_config.  

Power Consumption

Powered at 5V via 40-pin header on tobi board

Wifi AP mode and BT on, idle 400mA,  450mA under load
Stop hostapd -> idle drops to 292mA
rfkill does not seem to affect power usage
turning off bluetooth via gpio did not affect power usage
turning off wifi via gpio saw ~6mA drop in power usage
wifi in client mode only (ap off), see ~300mA just connected, 430mA when downloading a large file

earthstorm shows similar idle power consumption to ironstorm when power is turned off
on a summit expansion board (like tobi but no ethernet), idle power consumption is reduced to just 130mA 

In summary: 

  • With WiFi off, idle power consumption is ~300mA
  • 100% CPU use increases power consumption by ~50mA
  • WiFi draws up to ~100mA (always 100mA in AP mode, varies with distance and usage in client mode)
  • Further reductions in power use may be possible, but will require more work (possibly a custom kernel or u-boot modifications to disable the hdmi controller, etc) 

Duovero tests with no Wifi
idles around 230mA - not sure why this is so much lower than the overo,
jumps to around 500mA at full CPU usage, 380mA to fully utilize one core