Re: [PATCH] ext3: sreadahead hooks

[Arjan van de Ven <arjan@infradead.org>]

On Sun, 19 Oct 2008 23:42:05 +0200
Karel Zak <kzak@redhat.com> wrote:

> On Tue, Oct 14, 2008 at 04:49:51PM -0500, Eric Sandeen wrote:
> > Eric Sandeen wrote:
> > > Christoph Hellwig wrote:
> > >> On Tue, Oct 14, 2008 at 10:17:35AM -0400, Arjan van de Ven wrote:
> > >>> >From 3d7a0ca0ee8a755251251bd9ddca0866c25acdc2 Mon Sep 17
> > >>> >00:00:00 2001
> > >>> From: Arjan van de Ven <arjan@linux.intel.com>
> > >>> Date: Tue, 14 Oct 2008 10:12:08 -0400
> > >>> Subject: [PATCH] ext3: sreadahead hooks
> > >>>
> > >>> The sreadahead program, used to make the OS boot faster, needs
> > >>> to know in the approximate order in files are used during the
> > >>> boot process. This patch adds the ext3 hook for this
> > >>> functionality, basically it stores "jiffies" into the inode at
> > >>> allocation time, and exposes it via an EXT3 ioctl (yes I know
> > >>> but ioctl seems fitting for this).
> > >> Even if it's an ioctl there's absolutely no point in making this
> > >> fileystem specific.  Also the name is rather dumb and
> > >> non-descriptive.
> > > 
> > > I have to agree, both the ioctl name and the new field are not
> > > very descriptive - created_when sounds an awful lot like ctime
> > > but it's not.
> > > 
> > > and INODE_JIFFIES really doesn't mean anything at all w/o extra
> > > context. But I'm trying to think of some nice names.  :)
> > > 
> > > What about making a new struct inode field and doing this update
> > > in new_inode(), and making it a generic ioctl.  Are we ready to
> > > go that far?
> > 
> > Or, as I thought about/mentioned to hch, and I guess he and Arjan
> > already discussed... :)  why not just use tracing infrastructure to
> > get
> 
>  What do you mean by "tracing infrastructure"? Audit?

ftrace

I'll be looking into making that one work soon; it'll be... interesting
and more complex than this patch, but if that's what it takes...


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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