Re: [RFC] kernel facilities for cache prefetching

[Wu Fengguang <wfg@mail.ustc.edu.cn>]

Hi Pavel,

On Tue, May 02, 2006 at 09:10:01PM +0200, Pavel Machek wrote:
> > SOC PROPOSAL
> > 
> > 	Rapid linux desktop startup through pre-caching
> 
> Looks nice me...

Thanks.

> > SCHEME/GOAL
> > 	2) kernel module to query the file cache
> > 		- on loading: create /proc/filecache
> > 		- setting up: echo "param value" > /proc/filecache
> > 		- info query: cat /proc/filecache
> > 		- sample sessions:
> > 
> > 		# modprobe filecache
> > 		$ cat /proc/filecache
> > 		# file ALL
> > 		# mask 0
> > 		#
> > 		# ino	size	cached	status	refcnt	name
> > 		0	2929846	3181	D	1	/dev/hda1
> > 		81455	9	9	_	1	/sbin/init
> > 		......
> > 	
> > 		$ echo "file /dev/hda1" > /proc/filecache
> > 		$ cat /proc/filecache
> > 		# file /dev/hda1
> > 		# mask 0
> > 		#
> > 		# idx	len
> > 		0	24
> > 		48	2
> > 		53	5
> > 		......
> 
> Could we use this instead of blockdev freezing/big suspend image
> support? It should permit us to resume quickly (with small image), and
> then do readahead. ... that will give us usable machine quickly, still
> very responsive desktop after resume?

Sure. Indeed I have considered about the possibility to integrate my
work with the foresighted userland-swsusp idea. The added value of
this approach is that user-land tools can do all kinds of smart
processing of the contents, and present users with different policies.

Another imagined user of /proc/filecache is system adms :)

Wu