Re: IDE DMA Problems...system hangs

[Jasmeet Sidhu <jsidhu@arraycomm.com>]

 >>I've not changed anything related to DMA handling specifically. The current
 >>-ac does have a fix for a couple of cases where an IDE reset on the promise
 >>could hang the box dead. That may be the problem.

I tried the new patches (2.4.1-ac13) and it seemed very stable.  After 
moving about 50GB of data to the raid5, the system crashed.  here is the 
syslog... (the system had been up for about 20 hours)

Feb 14 03:48:53 bertha kernel: hdo: dma_intr: status=0x51 { DriveReady 
SeekComplete Error }
Feb 14 03:48:53 bertha kernel: hdo: dma_intr: error=0x84 { DriveStatusError 
BadCRC }
<snip - about 40 lines exact same hdo: error>
Feb 14 19:35:52 bertha kernel: hdo: dma_intr: error=0x84 { DriveStatusError 
BadCRC }
Feb 14 19:35:52 bertha kernel: hdo: dma_intr: status=0x51 { DriveReady 
SeekComplete Error }
Feb 14 19:35:52 bertha kernel: hdo: dma_intr: error=0x84 { DriveStatusError 
BadCRC }
Feb 14 20:13:06 bertha kernel: hdi: dma_intr: bad DMA status
Feb 14 20:13:06 bertha kernel: hdi: dma_intr: status=0x50 { DriveReady 
SeekComplete }

Feb 15 01:26:34 bertha kernel: hdo: dma_intr: status=0x51 { DriveReady 
SeekComplete Error }
Feb 15 01:26:34 bertha kernel: hdo: dma_intr: error=0x84 { DriveStatusError 
BadCRC }
Feb 15 01:26:34 bertha kernel: hdo: dma_intr: status=0x51 { DriveReady 
SeekComplete Error }
Feb 15 01:26:34 bertha kernel: hdo: dma_intr: error=0x84 { DriveStatusError 
BadCRC }
Feb 15 01:26:38 bertha kernel: hdo: dma_intr: status=0x51 { DriveReady 
SeekComplete Error }
Feb 15 01:26:38 bertha kernel: hdo: dma_intr: error=0x84 { DriveStatusError 
BadCRC }
Feb 15 01:45:06 bertha kernel: hdo: dma_intr: status=0x53 { DriveReady 
SeekComplete Index Error }
Feb 15 01:45:06 bertha kernel: hdo: dma_intr: error=0x84 { DriveStatusError 
BadCRC }
Feb 15 01:45:06 bertha kernel: hdo: dma_intr: status=0x51 { DriveReady 
SeekComplete Error }
Feb 15 01:45:06 bertha kernel: hdo: dma_intr: error=0x84 { DriveStatusError 
BadCRC }
Feb 15 01:45:06 bertha kernel: hdo: dma_intr: status=0x51 { DriveReady 
SeekComplete Error }
Feb 15 01:45:06 bertha kernel: hdo: dma_intr: error=0x84 { DriveStatusError 
BadCRC }
Feb 15 01:54:01 bertha kernel: hdg: timeout waiting for DMA
<SYSTEM FROZEN>

Jasmeet


At 08:54 PM 2/14/2001 +0000, Alan Cox wrote:
> > >You will get horribly bad performance off raid5 if you have stripes on 
> both
> > >hda/hdb  or hdc/hdd etc.
> >
> > If I am reading this correctly, then by striping on both hda/hdb and
> > /hdc/hdd you mean that I have two drives per ide channel.  In other words,
> > you think I have a Master and a Slave type of a setup?  This is
> > incorrect.  Each drive on the system is a master.  I have 5 promise cards
>
>Ok then your performance should be fine (at least reasonably so, the lack
>of tagged queueing does hurt)
>
> > ide chanel, the penalty should not be much in terms of performance.  Maybe
> > its just that the hdparam utility is not a good tool for benchamarking a
> > raid set?
>
>Its not a good raid benchmark tool but its a good indication of general 
>problems.
>Bonnie is a good tool for accurate assessment.
>
> > disable DMA if its giving it a lot of problems, but it should not hang.  I
> > have been experiencing this for quite a while with the newer
> > kernels.  Should I try the latest ac13 patch?  I glanced of the changes 
> and
> > didnt seem like anything had changed regarding the ide subsystem.
>
>I've not changed anything related to DMA handling specifically. The current
>-ac does have a fix for a couple of cases where an IDE reset on the promise
>could hang the box dead. That may be the problem.
>
> > Is there anyway I can force the kernel to output more messages...maybe 
> that
> > could help narrow down the problem?
>
>Ask andre@linux-ide.org. He may know the status of the promise support