Re: 2.4.17 RAID-1 EXT3 reliable to hang....

[Matti Aarnio]

On Mon, Jan 07, 2002 at 12:19:56AM -0800, Andrew Morton wrote:
> Matti Aarnio wrote:
> >   I have partial evidence that EXT3 may be part of the problem,
> >   as another machine with RAID-1 disks with EXT2 filesystems
> >   is not hanging up when running RedHat 2.4.16-0.9custom kernel.
> >   That another machine has, however, IDE disks.
> 
> I'd be surprised if an ext3 bug could cause a freeze as solid
> as this one.  ext3's write submission patterns are somewhat different
> from other filesystems, and we've exposed a few problem in underlying
> layers in the past because of this.  But who knows...
> 
> Have you enabled the NMI watchdog?  nmi_watchdog=1 on the LILO
> commandline?

# cat /proc/cmdline 
auto BOOT_IMAGE=up ro root=905 BOOT_FILE=/boot/vmlinuz-2.4.17up nmi_watchdog=1

  This is the apparently stable UP mode kernel, but this option
  has been present at all variants, although I don't recall of
  what the NMI count was previously -- same or lower than that
  of LOC count at  /proc/interrupts.

> Also, I'd be inclined to enable all the kernel debug options,
> including SLAB debug.

CONFIG_SCSI_DEBUG=y
CONFIG_JBD_DEBUG=y
# CONFIG_DEVFS_DEBUG is not set
# CONFIG_USB_STORAGE_DEBUG is not set
CONFIG_DEBUG_KERNEL=y
# CONFIG_DEBUG_HIGHMEM is not set
CONFIG_DEBUG_SLAB=y
CONFIG_DEBUG_IOVIRT=y
CONFIG_DEBUG_SPINLOCK=y
CONFIG_DEBUG_BUGVERBOSE=y

/Matti Aarnio