Re: SMP/509b/lockup bug

Richard B. Johnson (root@chaos.analogic.com)
Thu, 29 Apr 1999 11:58:45 -0400 (EDT)


On Thu, 29 Apr 1999, Wakko Warner wrote:

> > > The SMP/509b/lockup bug is still in 2.2.7 Is there a fix for this
> > > anywhere?
> >
> > Im still trying to figure out how it occurs. Fixing it will be easy - finding
> > the bug isnt so simple
>
> I have a question on this (since I have the same problem as well). Does it
> lockup only when there's lots of traffic? This card seems to cause
> collisions. If I transfer files at around 900kb/sec, the col light on the
> hub is 99% solid. (takes a 10ms break every now and then <g>)
>

The card can't 'cause' collisions. It only detects collisions. The
most common cause of collisions on networks that handle both 100 and
10 mbs are the boxes that translate between these two speeds. If you
have 100 mb/s into a switch, and it's feeding out to a 10/mbs line,
something has to give. The "give" is that the switch causes a collision
as a throttle. The hardware automatically retries up to 15 times
upon a collision so such throttling is transparent.

Cheers,
Dick Johnson
***** FILE SYSTEM WAS MODIFIED *****
Penguin : Linux version 2.2.6 on an i686 machine (400.59 BogoMips).
Warning : It's hard to remain at the trailing edge of technology.

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