[PATCH] repair: warn if running in low memory mode

[Christoph Hellwig]

On Tue, Jan 04, 2011 at 05:12:43PM +1100, Dave Chinner wrote:
> From: Dave Chinner <dchinner at redhat.com>
> 
> When checking large filesystems, xfs_repair makes an estimate of how
> much RAM it will need to execute effectively. If the amount of RAM
> is less than this, it reduces the bhash size and turns of
> prefetching, which will substantially slow down the repair process.
> Add a warning that indicates this is happening, along with a
> recommendation of how much RAM repair calculates it needs to run
> with prefetching enabled.
> 
> Signed-off-by: Dave Chinner <dchinner at redhat.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch at lst.de>

> +				do_warn(_("Not enough RAM available for repair "
> +					"to enable prefetching. This will be "
> +					"_slow_.\n"
> +					"You need at least %luMB RAM to run "
> +					"with prefetching enabled."),
> +					mem_used * 1280 / (1024 * 1024));

Maybe but the strings on a separate line to be easier readable and
greppable, e.g.:

				do_warn(
	_("Not enough RAM available for repair to enable prefetching. "
	  "This will be _slow_.\n"
	  "You need at least %luMB RAM to run with prefetching enabled."),