Re: [PATCH] laptop mode

[Jens Axboe <axboe@suse.de>]

On Thu, Oct 09 2003, Marcelo Tosatti wrote:
> 
> 
> On Thu, 9 Oct 2003, Jeff Garzik wrote:
> 
> > Linux Kernel Mailing List wrote:
> > > ChangeSet 1.1150.1.52, 2003/10/08 10:49:45-03:00, axboe@suse.de
> > > 
> > > 	[PATCH] laptop mode
> > > 	
> > > 	Hi Marcelo,
> > > 	
> > > 	Lots of people have been using this patch with great success, and it's
> > > 	been in the SuSE kernel for some months now too. It is also in the -benh
> > > 	ppc tree
> > > 	
> > > 	Basically, it introduces a write back mode of dirty and journal data
> > > 	that is more suitable for laptops. At the block layer end, it schedules
> > > 	write out of dirty data after the disk has been idle for 5 seconds.
> > > 	
> > > 	Laptop mode can be switched on and off with /proc/sys/vm/laptop_mode.
> > > 	There is also a block_dump sysctl, which if enabled will dump who
> > > 	dirties and writes out data. This is very helpful in pinning down who is
> > > 	causing unnecessary writes to the disk.
> > 
> > Red Hat just dropped this patch since it was suspected of data 
> > corruption ;-(
> 
> Uh, oh... Jens? 

See my previous mail. I don't see any problems with it, and I've
certainly not heard of (or experienced myself) problems with the patch.
I'm waiting for Jeff to expand on his mail, surely he/RH must know more
about this issue.

-- 
Jens Axboe