Re: [PATCH] Fix stack corruption in ext2fs server

[Samuel Thibault]

Richard Braun, le Wed 04 Jul 2012 08:22:13 +0200, a écrit :
> On Tue, Jul 03, 2012 at 09:13:36PM -0300, Samuel Thibault wrote:
> > Richard Braun, le Tue 03 Jul 2012 23:13:26 +0200, a écrit :
> > > * ext2fs/inode.c (diskfs_node_iterate): allocate the temporary node
> > > table from the heap instead of the stack.
> > 
> > That can be quite a lot for the stack indeed, thanks!
> 
> It's also quite a lot of heap too, and every 5 seconds. We should
> consider increasing the interval between global syncs to reduce the
> impact of this potentially heavy operation.

It would increase the amount of work you loose on crash. Did you measure
the CPU use that you get with a typical filesystem, by e.g. touching a
file every 4 seconds to trigger the sync all the time?

I guess the real fix would be to be better at knowing which inodes need
to be recorded, and filter on that.

Samuel