sio driver sucks

Mike Voorhis mvoorhis at
Mon Nov 13 07:03:16 PST 2006

Спартак Радченко wrote:
> I had serious problems with sio on Intel STL2 motherboard and recent
> stable. Massive silo overflows (modem was almost unusable) and at least
> 1 sio-related panic (spinlock held for more than 5 sec). Now I changed
> sio to uart ant it works like a charm. All problems gone.

Since we're posting annecdotes, I feel I should mention that I've used
"device sio" on a modem box used for remote-access serial terminal
connections for several years (FreeBSD-5 and FreeBSD-6) without any
trouble.  No crashes, no complaints, no lockups.

The machine is a Dell Optiplex gx260 machine with an attatched US
Robotocs modem.  The machine serves a few other network-related tasks as
well and has performed flawlessly.  Right now, the machine currently
runs 6.2-Prerelease from a few days ago.

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