Re: [9fans] venti+fossil woes

[Christopher Nielsen <cnielsen@pobox.com>]

On Tue, Nov 18, 2003 at 09:08:49AM -0500, Russ Cox wrote:
> Have you tried replacing the disk?  Since only one disk I/O
> is done at a time, I have a hard time believing that contention
> is causing them to time out.  Contention might cause them to
> take a while before they acquire the lock around the disk,
> but that isn't timed.

Changing the disk, currently, is not an option. There's
still data being written from fossil to venti from an
archival snapshot that starts up every time the machine
boots, albeit slowly and interspersed with fossil crashes.

On Tue, Nov 18, 2003 at 03:27:00PM +0000, Charles Forsyth wrote:
> it's probably just me, but i nearly always
> suspect software rather than hardware, until
> i'm absolutely sure (i have seen some botched
> hardware though).  i wonder whether
> the iBsy+ isn't a clue: it has got an interrupt,
> but the device is busy when the interrupt function
> starts, and it seems to happen (after some point)
> under load.  is the interrupt shared?
> are rwm and dma set?

I don't think the interrupt is shared. Both dma and rwm
are set for all the drives.

On Tue, Nov 18, 2003 at 10:36:55AM -0500, jmk@plan9.bell-labs.com wrote:
>
> I'd say that still points to a hardware problem. Can you tell
> us what
>       ATA controller (or which chipset it is in)
>       drive model numbers
>       the 'dev' lines printed at kernel boot for the drives are?

The controller is a Promise 100TX2 (PDC20268).

The drives are all Western Digital:
	2x WD1800JB venti arenas
	1x WD800JB fossil
	1x WD400JB venti index

The 'dev' lines from boot:
dev A0 port CCD8 config 427A capabilities 2F00 mwdma 0007 udma 203F
dev B0 port CCD8 config 427A capabilities 2F00 mwdma 0007 udma 203F
dev A0 port CCC0 config 427A capabilities 2F00 mwdma 0007 udma 203F
dev B0 port CCC0 config 427A capabilities 2F00 mwdma 0007 udma 203F

Thanks for the help/input, guys.

--
Christopher Nielsen
"They who can give up essential liberty for temporary
safety, deserve neither liberty nor safety." --Benjamin Franklin