Documentating patch for defaults/loader.conf

[Dmitry Morozovsky]

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< --

-- 
Sincerely,
D.Marck                                        [DM5020, MCK-RIPE, DM3-RIPN]
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*** Dmitry Morozovsky --- D.Marck --- Wild Woozle --- marck at FreeBSD.org ***
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