lkml.org 
[lkml]   [2002]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: 2.4: NFS client kmapping across I/O
On Tue, 29 Jan 2002, Hugh Dickins wrote:
> On Mon, 28 Jan 2002, Xeno wrote:
> >
> > Now I also have time to mention the other NFS client issue we ran into
> > recently, I have not found mention of it on the mailing lists. The NFS
> > client is kmapping pages for the duration of reads from and writes to
> > the server. This creates a scaling limitation, especially under
>
> You're right that kmap users should avoid holding them for very long,
> I'd certainly not discourage anyone from pursuing that effort.

Things like this would be fixed by having a kmap variant
which maps the pages into process-private space, kind of
like kmap_atomic(), but into a (4 MB sized?) part of
address space which is only visible within this process.

This would mean that each process can have a few MB of
kmap()d pages ... should be nice for things like having
copy_{to,from}_user "cache" the hot pages while keeping
longer term mappings from filling the global pool.

regards,

Rik
--
DMCA, SSSCA, W3C? Who cares? http://thefreeworld.net/

http://www.surriel.com/ http://distro.conectiva.com/

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:15    [W:0.439 / U:0.612 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site