🚀 go-pugleaf

Hi all,

this is a summary of the hints I've got for my problem with my unused but
enabled serial ports eating up my CPU:

1. Many others have the same problem.
2. It seems to be the case that the ports generate interrupts.
3. You can decrease CPU usage in several ways:
   a) don't enable the ports
   b) plug something into the ports that quiet them down (e.g. modem turned on,
      a terminal plugged in, logged in and then turned off)
   c) use the dsp together with additional hardware to get a high speed
      serial port that doesn't use up your CPU
4. The whole thing seems to be irrelevant of the OS version. I have 3.0, but
   it was that bad much earlier. That's easy to understand since it is a
   hardware problem.
5. If you think your '40 NeXT is standing still, a '30 one is running
   backwards.
6. A port that is configured to a higher baud rate is eating more CPU.
7. 19200 baud need approx. 30-40 percent of the CPU if it can get that much
8. A second port needs additional 30-40 percent.
9. A port configured to 1200 baud doesn't need any CPU, ps xu only shows 240K
   of RSIZE.
10.Modifying /etc/ttys and 'kill -HUP 1' takes effect immediately in both
   directions.
11.Ports without hardware flow control eat up the same amount of CPU.

Thanks to all who responded, even if there's no real solution,

Uli