>We are running inn on a 486 box, equipped with an EISA SCSI interface.
[...]
>Everything works fine under norman circumstances, but when there is a lot
>of SCSI activity, the machine crashes.  One day I was formatting two of
[...]
>ahe0: 274x Twin Channel, A SCSI Id=7, B SCSI Id=7, aic7770 >= Rev E, 4 SCBs
[...]

>Any ideas?  Should we replace the EISA controller with a PCI one?  Is there
>a reason why the ahe driver/hardware is slower than the 2940 board we
>have on another system (the difference is something like 3 MB/sec vs.
>7 MB/sec)?

I don't think it's EISA, specifically.  My BusLogic BT747s works
flawlessly on a 2/18 kernel.  And, I can get over 5MB/s sustained with
big blocks (iozone), or over 4MB/s (Bonnie 4200w/4514r), from ccd with
two SCSI drives, on a 486DX2/80, w/20MB RAM and 512K write-back cache.
This is with 3 SCSI hard drives and a SCSI CD-ROM on the chain.

I would suspect, first, SCSI bus termination and/or cabling.  Try
disconnecting and reconnecting the entire chain, making sure
everything is fastened correctly, termination is correct, and the
cable is not too long or damaged.

Failing that, I would suspect, secondly, the ahe driver.

-----------------------------------------------------------------------------
  Michael L. VanLoon                                 michaelv@HeadCandy.com
       --<  Free your mind and your machine -- NetBSD free un*x  >--
     NetBSD working ports: 386+PC, Mac 68k, Amiga, HP300, Sun3, Sun4,
                           DEC PMAX (MIPS), DEC Alpha, PC532
     NetBSD ports in progress: VAX, Atari 68k, others...
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