From: James Noyes (jnoyes-sml@retrogeeks.com)
Date: Wed Aug 11 2004 - 15:20:34 EDT
Ok, so I recently added a multi-disc CD-ROM changer to my Solaris 8 system to
facilitate access to some document repositories. The drive is configured to
present as target 6, luns 0-4. I added lun support to sd.conf for the proper
target, rebooted, and was presented with device entries for c2t6d0sN through
c2t6d4sN. All seemed well so far.
But vold refused to mount any discs I put in the drive. I thought the line:
use cdrom drive /dev/rdsk/c*s2 dev_cdrom.so cdrom%d
in vold.conf would match all these devices. The /dev/rdsk/c*s2 part certainly
SEEMS correct. Eventually, I was forced to add discrete lines to vold.conf:
use cdrom drive /dev/rdsk/c0t6d0s2 dev_cdrom.so cdrom0
use cdrom drive /dev/rdsk/c2t6d0s2 dev_cdrom.so cdrom1
use cdrom drive /dev/rdsk/c2t6d1s2 dev_cdrom.so cdrom2
use cdrom drive /dev/rdsk/c2t6d2s2 dev_cdrom.so cdrom3
use cdrom drive /dev/rdsk/c2t6d3s2 dev_cdrom.so cdrom4
use cdrom drive /dev/rdsk/c2t6d4s2 dev_cdrom.so cdrom5
to get it to work. My question is WHY? What was wrong with the wildcard
line? Is there a problem with vold? Do I need to apply a patch? Why does it
work with multiple non-wildcard lines? Will a wildcard line only match one
device? If so, what's the point of the wildcard in the first place?
Followup question: vold is multi-threaded, and appears to poll all of the
devices it's aware of in parallel. While this seems like a great idea at
first, on a multi-lun CD changer, it's not so great. The changer gets polled
for all of its luns, and ends up thrashing its way through them, switching
over and over and over. Disc 1, Disc 2, Disc 1, Disc 3, Disc 2, Disc 4, etc,
etc. It took almost 12 minutes on a bootup before vold quit thrashing and got
all the discs mounted (kernel usage was 50%, basically sucking up on one
entire cpu for this entire time). If I start with the drive empty and the
system up, I can insert discs one at a time, let each one mount, and it mounts
quickly and smoothly in a few seconds. But if the system reboots, it ends up
thrashing its way through the 5 discs again. Is there any way to convince
vold that these discs are all in a single mechanism, and to process them one
at a time, not in parallel?
Yes, I realize I could just manually manage the multi-disc changer and mount
the discs via a script on boot-up, but I was hoping to avoid that method if
possible. vold isn't a bad mechanism, and it would be nice to use it - at
least it would be if it was friendlier with multi-lun devices, that is.
I'll summarize any and all productive replies.
Cheers,
James Noyes
(jnoyes-sml@retrogeeks.com)
_______________________________________________
sunmanagers mailing list
sunmanagers@sunmanagers.org
http://www.sunmanagers.org/mailman/listinfo/sunmanagers
This archive was generated by hypermail 2.1.7 : Wed Apr 09 2008 - 23:29:16 EDT