Subject: Re: Alpha console weirdness
To: Edwin Foo <>
From: Chris G. Demetriou <>
List: port-alpha
Date: 05/26/1999 17:35:26
Edwin Foo <> writes:
> A few days ago I posted on port-alpha regarding a strange lockup condition
> on my AlphaPC164SX running release 1.4. To recap, my console will
> reproducibly freeze not respond to any further keyboard input if I use apps
> like vi,less,more, etc. The symptoms are increasing console "garbage" on the
> screen -- it basically looks like the letters are falling off my screen a la
> "The Matrix". =) Or maybe a better example is the Letter Invaders game from
> Marvin Bacon Teaches Typing.. anyways, I digress. Essentially, after a few
> screens of watching my screen fall apart, the console stops responding to
> commands. It is quite reproducible.

Is it that the letters are missing, misplaced, or what?

is there actually 'garbage' on the screen, i.e. non-letters, stuff
like that?

What terminal type are you using?  IIRC the standard console terminal
type was changed immediately preceding 1.4 (sun->vt<something>).
Using the wrong terminal emulation could possibly get you garbage like
you describe, and if the emulation code is buggy it could also lead to
hangs of various types.

> However, it doesn't seem to be limited to the console as of this morning; I
> was logged in via telnet and ran
> sup -v sup.conf
> the -v made it produce lots of messages, and soon enough, my telnet window
> was locked up solid too. Launching another telnet session and killing the
> offending csh process didn't convince my telnet client that the connection
> had been broken.

This is ... interesting.  Obviously it wouldn't be (just) console
terminal emulation code bugs if a telnet session shows a similar

I wonder if there's something weird going on in the tty code...

FWIW, i've not seen any of these types of problems on my alphas, but
then they're only AlphaStation 200s...

Chris Demetriou - -
Disclaimer: Not speaking for NetBSD, just expressing my own opinion.