> -----Original Message----- > From: Trond Myklebust [mailto:Trond.Myklebust@xxxxxxxxxx] > Sent: Tuesday, January 18, 2011 5:45 PM > To: Muntz, Daniel > Cc: matt@xxxxxxxxxxxx; rees@xxxxxxxxx; > androsadamson@xxxxxxxxx; linux-nfs@xxxxxxxxxxxxxxx; > bhalevy@xxxxxxxxxxx > Subject: RE: 4.1 no-pnfs mount option? > > On Tue, 2011-01-18 at 19:53 -0500, Daniel.Muntz@xxxxxxx wrote: > > > > > -----Original Message----- > > > From: Trond Myklebust [mailto:Trond.Myklebust@xxxxxxxxxx] > > > Sent: Tuesday, January 18, 2011 11:15 AM > > > To: Matt W. Benjamin > > > Cc: Muntz, Daniel; rees@xxxxxxxxx; androsadamson@xxxxxxxxx; > > > linux-nfs@xxxxxxxxxxxxxxx; Benny Halevy > > > Subject: Re: 4.1 no-pnfs mount option? > > > > > > On Tue, 2011-01-18 at 13:46 -0500, Matt W. Benjamin wrote: > > > > Hi, > > > > > > > > Isn't by mount a plausible way to select for pnfs > > > independent of debugging? Is it assured that a client > > > administrator would never reasonably wish to do this? > > > > > > "Why would an administrator never want to do this?" is > not a helpful > > > question. > > > > > > A more useful question is "what reason would you possibly have for > > > overriding the server's request that you do pNFS when > your client has > > > pNFS support?" What makes pNFS so special that we must allow > > > administrators to do this on a per-mount basis? > > > > By the same logic, why should a user be allowed to select > which version of NFS they use for mounting when the server > has a perfectly reasonable way of negotiating it? Getting to > choose v2 vs. v3 vs. v4 seems like much less of a distinction > than choosing between pNFS and no pNFS. Frankly, it never > even occurred to me that there wouldn't be a mount option to > make this choice. Enabling/disabling the layout driver > doesn't fit the existing model of choosing mount behavior, > and is a big hammer--it's all or nothing. > > > > Anyway, here's a use case: I'm working at an > HPC/gas+oil/satellite data site. We have an awesome pNFS > server for our big data and I want to access my big data with > pNFS. We have another server for homedirs, some big data, > and other stuff. Some mounts are fine with pNFS, others are > abysmal. So, I want to mount some directories with pNFS, and > some without pNFS, on the same client, independent of the > server configuration. > > mount -t nfs -overs=4,minorversion=0 foo:/ /bar > > Done... Any more questions? Several, but I'll stick to one rhetorical. Does NFSv4.1 have any features, other than pNFS, that are not in 4.0? > > -- > Trond Myklebust > Linux NFS client maintainer > > NetApp > Trond.Myklebust@xxxxxxxxxx > www.netapp.com > > > -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
