Re: cache limit

["J.A. Magallon" <jamagallon@able.es>]

On 08.19, Andrew Morton wrote:
> "J.A. Magallon" <jamagallon@able.es> wrote:
> >
> >  > It was not.  Instead we have fadvise.  So it would be appropriate to
change
> > 
> >  Does this work in 2.4 ?
> >  If not, any patch flying around ?
> 
> No.  It would be fairly messy to implement in 2.4 because 2.4 does not have
> the per-inode radix trees for pagecache.  The implementation would need to
> walk every page attached to the inode just to shoot down a single page. 
> And all of it underneath the global pagecache lock.
> 
> But it is certainly possible.
> 

So could O_STREAMING be included in 2.4, and let people do things like

#if 2.4
	fcntl(...O_STREAMING...)
#else
	posix_fadvise()
#endif

Or, if fadvise just fails with error code in 2.4, 
	if (fadvise()<0)
		fcntl(O_STREAMING)

Or even:
	fadvise()
	fcntl(O_STREAMING):
and let whatever succeed...

Or is it too dirt ?

TIA

-- 
J.A. Magallon <jamagallon@able.es>      \                 Software is like sex:
werewolf.able.es                         \           It's better when it's free
Mandrake Linux release 9.2 (Cooker) for i586
Linux 2.4.22-rc2-jam1m (gcc 3.3.1 (Mandrake Linux 9.2 3.3.1-1mdk))