Re: [NFS] NFS on loopback locks up entire system(2.6.23-rc6)?

From: Chakri n
Date: Fri Sep 21 2007 - 12:20:23 EST


Thanks.

I was using flock (BSD locking) and I think the problem should be
solved if I move my application to use POSIX locks.

And any option to avoid processes waiting indefinitely to free pages
from NFS requests waiting on unresponsive NFS server?

Thanks
--Chakri

On 9/21/07, Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> wrote:
> On Thu, 2007-09-20 at 20:12 -0700, Chakri n wrote:
> > Thanks Trond, for clarifying this for me.
> >
> > I have seen similar behavior when a remote NFS server is not
> > available. Many processes wait end up waiting in nfs_release_page. So,
> > what will happen if the remote server is not available,
> > nfs_release_page cannot free the memory since it waits on rpc request
> > to complete, which never completes and processes wait in there for
> > ever?
> >
> > And unfortunately in my case, I cannot use "mount --bind". I want to
> > use the same file system from two different nodes, and I want file &
> > record locking to be consistent. The only way to make sure locking is
> > consistent is to use loopback NFS on 1 host and NFS mount the same
> > file system on other nodes, so that NFS server ensures file & record
> > locking to be consistent. Is there any alternative to this?
> >
> > Is it possible or any efforts to integrate ext3 or other local file
> > systems locking & network file system locking, so that user can use
> > "mount --bind" on local host and NFS mount on remote nodes, but file &
> > record locking will be consistent between both the nodes?
>
> Could you be a bit more specific? Is the problem that your application
> is using BSD locks (flock()) instead of POSIX locks?
>
> Cheers
> Trond
>
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/