kern/57174: 4.9-PRERELEASE panic: ata_dmasetup:

[Eugene Grosbein]

dmitry at atlantis.dp.ua wrote:
> 
> Hello!
> 
>  I'm curious whether this issue would be critical for ANY ata(4)-system.
> So (to the PR originator): Eugene, could you try your experiment with
> tagged queueing turned off (hw.ata.tags=0)?

I've tried. It does not panic with hw.ata.tags=0, 
glimpseindex took more than a hour to complete.
This time CPU utilization was about 50% only
and 'systat -vm 3' have shown 100% of hard drive usage.

So Tagged Queueing may be guilty (again).

Eugene Grosbein