Subject: Why "usl_detachack: not detaching"?
To: Tor Stormwall <tor@stormwall.org>
From: Stephen Ma <stephenm@employees.org>
List: tech-x11
Date: 01/09/2003 15:02:55
>>>>> "Tor" == Tor Stormwall <tor@stormwall.org> writes:

Tor> When I compile a program in a xterm or similar or run a program
Tor> that uses much of the computers memory and try to hit
Tor> Ctrl-Alt-F2, X refuses to let me out to console mode.

Tor> Every time this happens I get
Tor> Jan 6 12:41:39 ring /netbsd: usl_detachtimeout
Tor> Jan 6 12:41:41 ring /netbsd: usl_detachack: not detaching
Tor> from /var/log/messages.

Tor> What can I do to solve this? I'm using XFree86 4.2.0 on a i386.

What's happening is the the X server has been paged out due to the
memory load. When you try to switch to another VT, the X server
doesn't respond quickly enough to the console's VT switch request, so
the request gets cancelled (which is why the usl_detach* messages get
generated).

Possible solutions: hit Ctrl-Alt-F2 again after about 5-10 seconds
(according to the log, it's taking around 7 seconds for the X server
to be paged back in). Alternatively, you can change the VT switch
timeout to a longer value - it defaults to 5 seconds. This can be
changed in your kernel config file with "options
WSCOMPAT_USL_SYNCTIMEOUT=10".

- S