Heads up: e2fsprogs-1.42-WIP-0702 pushed to rawhide

[Richard W.M. Jones]

On Wed, Oct 05, 2011 at 09:58:59AM -0500, Eric Sandeen wrote:
> right; for large ext4 fs use (or testing), try 
> 
> # mkfs.ext4 -E lazy_itable_init=1 /dev/blah
>
> this will cause it to skip inode table initialization, and speed up
> mkfs a LOT.  It'll also keep sparse test images smaller.
>
> IMHO this should probably be made default above a certain size.

You almost preempted my question: Could I use this for every ext4
filesystem I make?  Honestly from a virt / libguestfs p.o.v. it sounds
like something we should always do.

> The tradeoff is that inode table initialization happens in
> kernelspace, post-mount - with efforts made to do it in the
> background, and not impact other I/O too much.

Is there a circumstance where this is bad?  I'm thinking perhaps a
case where you create a filesystem and immediately try to populate it
with lots of files.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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