[xfs-masters] Re: 2.6.19-rc6 : Spontaneous reboots, stack overflows - seems to implicate xfs, scsi, networking, SMP

[Al Viro <viro@xxxxxxxxxxxxxxxx>]

On Wed, Nov 22, 2006 at 08:10:13PM -0800, David Miller wrote:
> From: David Chinner <dgc@xxxxxxx>
> Date: Thu, 23 Nov 2006 12:18:09 +1100
> 
> > So, assuming the stacks less than 32 bytes are 32 bytes, we've got
> > 1380 bytes in the XFS stack there, 
> 
> On sparc64 just the XFS parts of the backtrace would be a minimum of
> 2816 bytes (each function has a minimum 8 * 16 byte stack frame, and
> there are about 22 calls in that trace).  It's probably a lot more
> with local variables and such.
> 
> It's way too much.  You guys have to fix this stuff.
> 
> If TCP's full send and receive path can be done in less function
> calls, XFS can allocate blocks in less too.
> 
> I would even say 10 function calls deep to allocate file blocks
> is overkill, but 22 it just astronomically bad.

Especially since a large part is due to cxfs...