Documentating patch for defaults/loader.conf

[Alexander Motin]

On 22.08.2011 23:10, Dmitry Morozovsky wrote:
> On Mon, 22 Aug 2011, Kostik Belousov wrote:
>>> any objections for this simple patch?
>>>
>>> (we stumped into this yesterday, and no easy founded answers even on Google
>>> except the single FreeBSD Forums thread was found)
>>
>> I do not think that the wording in right, but I am not CAM expert by any
>> measure. From my reading of the code, it is a hook to delay the root mount,
>> not to delay CAM bus registration. It would be better if you get the scsi@
>> or mav@ (author of the tunable) review.
>
> I based the comment on existing comment to the tunable in cam_xpt.c:
>
> cam_xpt.c:TUNABLE_INT("kern.cam.boot_delay",&xsoftc.boot_delay);
> cam_xpt.c:SYSCTL_INT(_kern_cam, OID_AUTO, boot_delay, CTLFLAG_RDTUN,
> cam_xpt.c:&xsoftc.boot_delay, 0, "Bus registration wait time");
>
>
> Alexander, colleagues, your thought on the following patch?
>
> -- 8<  --
> Index: boot/forth/loader.conf
> ===================================================================
> --- boot/forth/loader.conf      (revision 224542)
> +++ boot/forth/loader.conf      (working copy)
> @@ -109,6 +109,8 @@
>   #kern.ncallout=""              # Set the maximum # of timer events
>   #kern.ngroups="1023"           # Set the maximum # of supplemental groups
>   #kern.sgrowsiz=""              # Set the amount to grow stack
> +#kern.cam.boot_delay="10000"   # CAM bus registration delay (in ms),
> +                               # useful for USB sticks as root
>   #kern.cam.scsi_delay="2000"    # Delay (in ms) before probing SCSI
>   #kern.ipc.maxsockets=""                # Set the maximum number of sockets
> avaliable
>   #kern.ipc.nmbclusters=""       # Set the number of mbuf clusters
> -- 8<  --

Yes, I agree that wording is not perfect. It is not a delay of the bus 
registration, but instead boot delay for the bus registration. Original 
sysctl description is closer to the right meaning.

-- 
Alexander Motin