3C905C and error e401 : problem solved

[francois.cami@supelec.fr]

Hi Mr Morton and all linux-kernel,

I have been experimenting with the 3C905C, trying
to get rid of the annoying e401 error (too much work
in interrupt).

I've tried using 64 as max_interrupt_work 
and it solves completely
the e401 problem on this particular machine :

- yoda.rez-gif.supelec.fr (dns/proxy for 500 clients,
  on a 10Mbits/s direct Internet connexion, local
  network is 100Mbits/s)
	ASUS P2B-DS
	dual PII-350
	512MB RAM (2*128+1*256)
	3*IBM 18GB 10KT U2W SCSI 
	3C905C
	S3 Virge
Linux Slackware-current, 2.2.19 or 2.4.4 both built for smp
with APIC. 

Before setting max_interrupt_work at 64, the e401 error
could occur 20 times a day.
Now it doesn't occur anymore.

I have waited for a long time to test that on the
SMP PC because it is critical for our network.
I have tried to link these e401 messages with another
activity on the PC, like heavy I/O, to no avail. The
3C905C does 10 times as many interruptions as the SCSI
controller does. Lowering the max_interrupt_work creates
a lot more errors in the logs (all are e401).


On that second PC, the message still appears (very rarely though,
about once in two or three days. I cannot relate those
occurences to anything). It used to appear very often
(about 40 times a day).
I have tried to put the machine under stress (4 heavy FTP
transfers at once, each 400MB long, with 4 different
clients, connected in 100 MBits FD). The e401 message
has not appeared... I'm a bit at a loss here.

- lando.rez-gif.supelec.fr (FTP for the same network)
	ABIT LX6
	PII300
	128MB RAM
	IBM 8.4GB IDE (1st Master) 
         + Maxtor 60GB IDE (2nd Master)
	3C905C
	S3 Virge
Linux Slackware-current, 2.4.4, ProFTPD

All our network is 100MBits Full Duplex, switched
with 3COM switches.

Best regards, thanks for all your work

François Cami