Re: 2.4.20 instability on bigmem systems?

[William Lee Irwin III]

On Thu, Mar 13, 2003 at 04:27:22PM -0800, Gregory K. Ruiz-Ade wrote:
> The primary problem:  Whenever any process (or set of processes) initiates 
> intensive disk I/O, the system grinds to a halt, kswapd and kupdated 
> consume upwards of 40% to 60% CPU each, and system load averages can jump 
> upwards of 21.00.  The problem can be replicated with a simple find command 
> ("find / -print" seems to do it nicely).
> I have had two rather painful nights dealing with this (Monday and Tuesday 
> nights).  Luckily, I have a serial null-modem cable rigged up between the 
> troubled server and another server, and was able to capture all the info 
> from the Magic Sysrq commands that I could.
> Full details are at http://castandcrew.com/~gregory/lkmlstuff/burpr/2.4.20

Hmm, slabinfo would be very helpful, as well as meminfo.

On Thu, Mar 13, 2003 at 04:27:22PM -0800, Gregory K. Ruiz-Ade wrote:
> I've included the kernel config, the kernel and initrd images, the system 
> map file, output from "ps auxfww" and a couple screen scrapings from top, 
> and captures from magic sysrq commands from both crashes.
> I had problems like this with 2.4.19, and was directed to apply a patch to 
> inode.c, which appears to be part of a patch set for 2.4.19pre9aa2.  I've 
> archived it at:
> http://castandcrew.com/~gregory/lkmlstuff/burpr/2.4.19/patches/10_inode-highmem-2
> For 2.4.19, this solves _most_ of the stability issues, but I still have to 
> work with the LVM people and possibly whomever is responsible for the VM in 
> 2.4.19/2.4.20 to track down some kernel oopses (possibly a seperate 
> problem.)
> I will happily provide whatever other information is needed, though my 
> opportunities to test things on the machine in question is limited by the 
> fact that it's a production server.

You might need bh stuff (memclass-related or something like it) if it's
general disk io. Can't be too sure until slabinfo + meminfo materialize.

-- wli