ian, you, mike and i should should discuss transport multiplexing offline. my transport switch patches are here, if you want to review them:
http://troy.citi.umich.edu/~cel/linux-2.6/2.6.9-a/release-notes.html > -----Original Message----- > From: Ian Kent [mailto:[EMAIL PROTECTED] > Sent: Tuesday, January 18, 2005 11:21 PM > To: Mike Waychison > Cc: autofs mailing list; [EMAIL PROTECTED]; David Meleedy > Subject: Re: [autofs] BUG: autofs4 + cd > /net/<Netapp>/vol/vol[0-3] = portusage problems > > > On Tue, 18 Jan 2005, Mike Waychison wrote: > > > -----BEGIN PGP SIGNED MESSAGE----- > > Hash: SHA1 > > > > Ian Kent wrote: > > > On Tue, 18 Jan 2005, Jeff Moyer wrote: > > > > > > > > >>==> Regarding Re: [autofs] BUG: autofs4 + cd > > >>/net/<Netapp>/vol/vol[0-3] = port usage problems; Ian Kent > > >><[EMAIL PROTECTED]> adds: > > >> > > >>raven> On Mon, 17 Jan 2005, Jeff Moyer wrote: > > >> > > >>>>==> Regarding Re: [autofs] BUG: autofs4 + cd > > >>>>/net/<Netapp>/vol/vol[0-3] = port usage problems; > [EMAIL PROTECTED] > > >>>>adds: > > >>>> > > >> > > >>raven> On Fri, 14 Jan 2005, David Meleedy wrote: > > >> > > >>>>>>Ian, I have installed the multi-over patch into our > version of > > >>>>>>the >> > > >>>> > > >>>>automounter 4.1.3-67 (with updated large-program-map > patch) and so > > >>>>far > > >>>> > > >>>>>>everything looks great! I am going to test our > machines for a > > >>>>>>longer period of time and make sure everything looks > stable, but > > >>>>>>so far, so good! > > >>>> > > >>raven> That sounds very encouraging. Great! > > >> > > >>>>Very encouraging indeed. Good catch, Ian! > > >>>> > > >>>> > > >>>>>>It seems to have eliminated the "BUG" message in the messages > > >>>>>>file, > > >>>> > > >>>>and >> it seems as though the automounter can unmount > /net/aflac > > >>>>which it was >> not able to do in the past during a reboot. I > > >>>>suspect that this means >> it will use a lot less ports, and I > > >>>>might not even need the kernel patch >> (given the > small amount of > > >>>>mounts we actually use) > > >>>>-- I am testing this >> as well. > > >>>> > > >> > > >>raven> The BUG messages were placed there to identify > this happening > > >>raven> as this problem has come up in various forms several times. > > >> > > >>raven> In this case it appears to be caused by the order in which > > >>raven> the mounts are done (ie. received from auto.net). > Given that > > >>raven> current autofs implementation of multi-mounts must handle > > >>raven> them as a single unit, nested filesystem mounts, > made in the > > >>raven> wrong order, cause overmounting which caused the umount > > >>raven> problem. > > >> > > >>raven> Perhaps. > > >> > > >>raven> Depends on whether the mount program has the patch which > > >>raven> probes the NFS server. The port usage problem > still remains > > >>raven> and I expect it will continue to cause problems for us one > > >>raven> way or another. Hopefully it will be addressed in the near > > >>raven> future. > > >> > > >>>>Hmm, I wonder what probing it actually does. I'll have > a look and > > >>>>see if we can change the probe code to use non-reserved ports. > > >> > > >>raven> I looked at the code in an FC2 mount and found that it did > > >>raven> quite a bit of probing. > > >> > > >>[snip] > > >> > > >>raven> This just means that we need to get a handle on the > > >>raven> objections to RPC transport multiplexing and get it done. > > >> > > >>I forwarded Mike's patch off to Steve Dickson. However, with the > > >>caveats he listed, I'm not optimistic. > > > > > > > > > Neither am I. The patch that Trond originally did is probably a > > > better > > > starting point. > > > > Which patches are we referring to by chance? I'm guessing the xprt > > stuff? I don't know of Trond's patches that do the same. > > Trond never finished them. He probably got too much flack about > scalability and request slot exhastion and gave up on it. > > He reffered to them in a previous discussion on the same > topic and said > that if anyone wanted to port them to a current kernel and > finish them > they were welcome. > > So I did that at the time for vanila kernels (2.4.22 amd > 2.6.0) but had no > confidence in my work as my understanding of the RPC > subsystem is fairly > poor and was worse at the time. I asked Trond to check them > but he clearly > didn't have time. > > If you wish to look for youself they can be found at > http://www.kernel.org/pub/kernel/people/raven/nfs > > The patch takes account of other kernel RPC users, lockd and portmap. > > Basically it moves the transport allocation into the > transmit/receive FSM > using a get/put mechanism, requiring only that kernel RPC > users allocate > the client struct. It looks to me like this approach would > lend itself to > dynamic allocation of additional transports upon request slot > exhaustion. > > I spent some time checking this last weekend and it looks > like porting > them to current kernels is not too hard but will be tedious. > > Mind you I've transcribed these from Tronds' original patch and there > could be errors in that work so they will need to be sanity checked > anyway. > > I'm keen to spend some more time on this, so perhaps between > this and what > you have already done we can get something that will make it > into the RPC > subsystem. Stranger things have happened. > > > > > > > > > There's quite a bit to do meantime such as, general testing, > > > scalability > > > testing, dynamically allocating a new transport if a > request slot can't be > > > allocated and so on. > > > > > > There will be quite a bit more discussion on this I expect. > > > > > > What is Steves responsibility here? > > > > > > Ian > > > > > > _______________________________________________ > > > autofs mailing list > > > [email protected] > > > http://linux.kernel.org/mailman/listinfo/autofs > > > > > > - -- > > Mike Waychison > > Sun Microsystems, Inc. > > 1 (650) 352-5299 voice > > 1 (416) 202-8336 voice > > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > NOTICE: The opinions expressed in this email are held by > me, and may > > not represent the views of Sun Microsystems, Inc. > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > -----BEGIN PGP SIGNATURE----- > > Version: GnuPG v1.2.5 (GNU/Linux) > > Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org > > > > iD8DBQFB7UgtdQs4kOxk3/MRAjaqAJwIYgp0GjlAH2X9Jl/wCs885AIRVgCfYBqI > > 0nJ1cZt77/sebi1MjVlV7pk= > > =n93V > > -----END PGP SIGNATURE----- > > > > _______________________________________________ > autofs mailing list > [email protected] > http://linux.kernel.org/mailman/listinfo/autof> s > _______________________________________________ autofs mailing list [email protected] http://linux.kernel.org/mailman/listinfo/autofs
