[Gambas-user] High CPU usage when using serialport component

[Christer Johansson]

Noticed a very high CPU usage when using the serialport on a
Raspberry Pi running Debian Squeeze and trying to understand
whats causing it...

Just opening the serialport in the SerialPort demo takes 12-26%
depending on if using the built in serialport (/dev/ttyAMA0) or
if using a standard USB to TLL converter (/dev/ttyUSB0)

Serial Port Demo - /dev/ttyAMA0 opened @ 9600 8N1

   PID USER     PRI  NI  VIRT   RES   SHR S CPU% MEM%   TIME+  Command
  22287 christer  20   0 30720  9284  7504 S 12.0  3.9  0:09.30 gbr3
/home/christer/Gambas 3/Projekt/SerialPort/SerialPort.gambas

Serial Port Demo - /dev/ttyUSB0 opened @ 9600 8N1.

   PID USER     PRI  NI  VIRT   RES   SHR S CPU% MEM%   TIME+  Command
  23970 christer  20   0 30852  9372  7524 S 26.0  4.0  1:05.15 gbr3
/home/christer/Gambas 3/Projekt/SerialPort/SerialPort.gambas

Above readings are from htop and attached are also a screenshot
showing the CPU graph in Xfce.

Are anyone of you other Raspberry Pi users experiencing the same?

The serialport seems to work OK (at least on 9600 8N1) but it seems
quite wierd that so much CPU is used just for listening on a serialport,
any ideas?

/CJ
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