[lkml]   [1999]   [May]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: Linux & NFS caching: reducing TCO
On Wed, 12 May 1999, Colin Hirsch wrote:

> In such a case it might be necessary to let the server be able to send a
> kind of invalidate message to the clients if something changes (I
> thought of keeping data in cache for tens of minutes). This whole setup
> obviously relies on only few changes and only makes sense for e.g. /usr
> but _not_ /home.

The problem with this is that NFS is generaly considered stateless. Sure,
you can do NFS over TCP (though IIRC it's rather minimal in current Linux
kernels), but that's not really enough state AFAIK.

In your case, I'd suggest using Coda. I was talking today with one of the
guys that worked on Coda a while back about its problems and
disadvantages, but your specific case just happens to be precisely what
Coda was designed for...

I assume all the client machines still have disks from when they weren't
diskless? What you do is use nfsroot to boot them, start up Coda and link
it to the Coda server, use the local disk for caching/hoarding, and
symlink /usr and /home to /coda/usr and /coda/home. All should be well,
network traffic drops to very little because the clients will cache most
or all of /usr on their local disks, and everything stays nicely in sync.

I've been thinking about doing a similar thing with a robot I'm building,
but there I have the problem of needing to do the entire thing without a
spinning disk, and without NFS entirely once it's booted. A lot messier
than what you'd be up against, trust me... ;-)

Coda's home page is


Erik Walthinsen <> - Staff Programmer @ OGI
Quasar project -
Video4Linux Two drivers and stuff -
/ \ SEUL: Simple End-User Linux -
| | M E G A Helping Linux become THE choice
_\ /_ for the home or office user

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:51    [W:0.080 / U:15.128 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site