"Dupuis, Don" wrote:
>
> I have already sent a patch to Alan and Linus on this issue. Linus has
> never responed and Alan said he would look into it in the middle of April.
> Nothing is new at this point
>
> -----Original Message-----
> From: PhiloVivero [mailto:pvspam-dntrepl@hacklab.net]
> Sent: Sunday, April 22, 2001 12:12 AM
> To: linux-kernel@vger.kernel.org
> Cc: sebastien.godard@wanadoo.fr; timb@claire.org; axboe@suse.de;
> phiviv@hacklab.net
> Subject: Device Major max and Disk Max in 2.4.x kernel
>
> I have a problem. Trying to write an iostat for Linux (or use an existing
> one):
>
> >From the kernel source:
>
> [/usr/src/linux-2.4.2/include/linux] :) grep DK_MAX *.h
> kernel_stat.h:#define DK_MAX_MAJOR 16
> kernel_stat.h:#define DK_MAX_DISK 16
>
> What to notice: MAJOR and DISK max are 16.
>
> Again, from the kernel source:
>
> [/usr/src/linux-2.4.2/fs/proc] :) grep -15 DK_MAX proc_misc.c
> <snip>
> for (major = 0; major < DK_MAX_MAJOR; major++) {
> for (disk = 0; disk < DK_MAX_DISK; disk++) {
> int active = kstat.dk_drive[major][disk] +
> kstat.dk_drive_rblk[major][disk] +
> kstat.dk_drive_wblk[major][disk];
> if (active)
> len += sprintf(page + len,
> "(%u,%u):(%u,%u,%u,%u,%u) ",
> major, disk,
> kstat.dk_drive[major][disk],
> kstat.dk_drive_rio[major][disk],
> kstat.dk_drive_rblk[major][disk],
> kstat.dk_drive_wio[major][disk],
> kstat.dk_drive_wblk[major][disk]
> );
> }
> }
>
> What to notice: We are looping up to the DK_MAX_MAJOR and DK_MAX_DISK. What
> this means is, any major >16 or disk >16 won't be listed in /proc/stat under
> the "disk_io" section.
>
> Problem. On my system, which I figure is not too uncommon, I have several
> partitions on two hard drives and a CDROM. They are configured thusly:
>
> # cat /proc/partitions
> major minor #blocks name
> 3 0 20094480 hda
> 3 1 6313513 hda1
> 3 2 401625 hda2
> 3 3 13374112 hda3
> 3 64 4497152 hdb
> 56 0 45034920 hdi
> 56 1 22490968 hdi1
> 56 2 22539195 hdi2
>
> What to notice: I have a drive on /dev/hdi (never mind why, it actually
> works)
> that is block major 56. Not only that, my cdrom device on /dev/hdb is block
> major 3, but minor number 64. I am assuming for disks, minor == disk. Sorry
> if
> this is an incorrect assumption.
>
> No stats for /dev/hdi nor /dev/hdb ever show up in /proc/stat. Only for
> /dev/hda. On my other 2.4.2 system, with multiple hard drives under 16/16,
> I get multiple devices under /proc/stat.
>
> The patch seems relatively easy. Change linux/include/linux/kernel_stat.h to
> allow block major up to 56 (in my case... 64 in general???) and disks up to
> 64
> (in my case).
>
> But we might need more than 64 disks on a block major (there are MANY snips
> in
> this so-called cut 'n' paste, because I figure you don't want to see them
> all):
>
> # l /dev/hd* | sort -n
> brw-rw---- 1 root disk 3, 79 Feb 22 08:57 /dev/hdb15
> brw-rw---- 1 root disk 3, 80 Feb 22 08:57 /dev/hdb16
> brw-rw---- 1 root disk 22, 79 Feb 22 08:57 /dev/hdd15
> brw-rw---- 1 root disk 22, 80 Feb 22 08:57 /dev/hdd16
> brw-rw---- 1 root disk 33, 79 Feb 22 08:57 /dev/hdf15
> brw-rw---- 1 root disk 33, 80 Feb 22 08:57 /dev/hdf16
> brw-rw---- 1 root disk 34, 79 Feb 22 08:57 /dev/hdh15
> brw-rw---- 1 root disk 34, 80 Feb 22 08:57 /dev/hdh16
> brw-rw---- 1 root disk 56, 126 Mar 25 17:14 /dev/hdj62
> brw-rw---- 1 root disk 56, 127 Mar 25 17:14 /dev/hdj63
>
> What to notice: We have disks up to 127. I never see any block major over 64
> on my system. The /dev/hdj device isn't used on my system. /dev/hdi and
> /dev/hdj belong to a Promise RAID controller on a new-ish
> ASUS AMD motherboard.
>
> Let me know if I can be of further service. I must bashfully admit that I'm
> not enough of a guru to recompile my kernel anymore, or I'd tweak the
> kernel_stat.h file and recompile myself to test this.
>
> This is just hazy recollection, but I think the 2.2.x kernels have the same
> problem.
Just never thing about those stats - they just broken by design.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Mon Apr 23 2001 - 21:00:46 EST