It will not help if the request is not resubmitted to the FSAL. Marc.
From: "Frank Filz" <ffilz...@mindspring.com> To: Marc Eshel/Almaden/IBM@IBMUS Cc: "'nfs-ganesha-devel'" <nfs-ganesha-devel@lists.sourceforge.net> Date: 09/07/2016 04:18 PM Subject: RE: [Nfs-ganesha-devel] NLM async locking I changed it so we don't take the lock off the list when it find the blocked lock entry in the blocked lock list. It then removes it from the list only if sending the async grant succeeds. It probably needs some tweaking, but it SHOULD help. Frank > -----Original Message----- > From: Marc Eshel [mailto:es...@us.ibm.com] > Sent: Wednesday, September 7, 2016 4:11 PM > To: Frank Filz <ffilz...@mindspring.com> > Cc: 'nfs-ganesha-devel' <nfs-ganesha-devel@lists.sourceforge.net> > Subject: RE: [Nfs-ganesha-devel] NLM async locking > > Just looking at the code I don't see where you retry the lock request from > the FSAL which is required to add it back to the FSAL queue. > Am I missing something? > Marc. > > > > From: "Frank Filz" <ffilz...@mindspring.com> > To: Marc Eshel/Almaden/IBM@IBMUS > Cc: "'nfs-ganesha-devel'" <nfs-ganesha-devel@lists.sourceforge.net> > Date: 09/07/2016 03:57 PM > Subject: RE: [Nfs-ganesha-devel] NLM async locking > > > > Marc, > > Could you try the top commit in this branch: > > https://github.com/ffilz/nfs-ganesha/commits/async > > It may not be the complete solution, but I think it will help your > scenario. > > I need to do more work on async blocking locks... > > And it looks like without async blocking lock support, Ganesha doesn't > handle the case where a lock blocks on a conflicting lock from outside the > Ganesha instance. I will be looking at implementing my thread pool idea > that > I modeled in the multilock tool. > > Frank > > > -----Original Message----- > > From: Frank Filz [mailto:ffilz...@mindspring.com] > > Sent: Wednesday, September 7, 2016 9:42 AM > > To: 'Marc Eshel' <es...@us.ibm.com> > > Cc: 'nfs-ganesha-devel' <nfs-ganesha-devel@lists.sourceforge.net> > > Subject: Re: [Nfs-ganesha-devel] NLM async locking > > > > Ok, I'm not sure this ever worked right... > > > > With the lock available upcall, we never put the lock back on the > blocked > lock > > list if an attempt to acquire the lock from the FSAL fails... > > > > So the way the lock available upcall is supposed to work: > > > > Client requests conflicting lock > > Blocked lock gets registered by FSAL > > SAL puts lock on blocked lock list > > Time passes > > FSAL makes lock available upcall > > SAL finds the blocked lock entry in the blocked lock list SAL makes a > call > to > > FSAL to attempt to acquire the lock Assume that fails (in the example, > > because multiple conflicting locks got > > notified) > > SAL puts the lock BACK on the blocked lock list (this step is missing) > and > all is > > well.... > > Time passes > > FSAL makes lock available upcall > > SAL finds the blocked lock entry in the blocked lock list SAL makes a > call > to > > FSAL to attempt to acquire the lock Lock is granted by FSAL SAL makes > async > > call back to client If THAT fails, SAL releases the lock from the FSAL > and > > disposes of the lock entry and all is well If THAT succeeds, the lock is > > completely granted and all is well > > > > I also see that if the client retries the lock before it is granted, we > don't > > remove the lock entry from the blocked lock list... I don't think that > will ever > > cause a problem but we should clean that up also... > > > > Let me try a patch to fix... > > > > Frank > > > > > -----Original Message----- > > > From: Marc Eshel [mailto:es...@us.ibm.com] > > > Sent: Tuesday, September 6, 2016 9:34 PM > > > To: Frank Filz <ffilz...@mindspring.com> > > > Cc: 'nfs-ganesha-devel' <nfs-ganesha-devel@lists.sourceforge.net> > > > Subject: RE: NLM async locking > > > > > > Did you get a chance to look at this problem? > > > Marc. > > > > > > > > > > > > From: "Frank Filz" <ffilz...@mindspring.com> > > > To: Marc Eshel/Almaden/IBM@IBMUS > > > Cc: "'nfs-ganesha-devel'" > <nfs-ganesha-devel@lists.sourceforge.net> > > > Date: 08/29/2016 02:37 PM > > > Subject: RE: NLM async locking > > > > > > > > > > > > > I see the following failure: > > > > 1. Get conflicting locks from 3 clients > > > > cli 1 gets 0-100 > > > > cli 2 is blocked on 0-1000 > > > > cli 3 is blocked on 0-10000 > > > > 2. cli 1 unlocks > > > > up-call for cli 2 and 3 to retry > > > > cli 2 gets 0-1000 > > > > cli 3 is blocked on 0-1000 > > > > 3. cli 2 unlocks > > > > up-call for cli 3 but Ganesha fails > > > > > > > > /* We must be out of sync with FSAL, this is fatal */ > > > > LogLockDesc(COMPONENT_STATE, NIV_MAJ, "Blocked Lock Not > > > > Found for" > > > > , > > > > obj, owner, lock); > > > > LogFatal(COMPONENT_STATE, "Locks out of sync with FSAL"); > > > > > > > > I think the problem is in step 2, after cli 3 failed for the second > > > > time > > > it is not > > > > put back in queue, the sbd_list. > > > > > > > > Can you please confirm this logic is very complicated. > > > > > > That sounds like a likely problem. I'd have to dig into the code to > > > see > > why... > > > May take me a day or two to investigate. > > > > > > Frank > > > > > > > > > > > > --- > > > This email has been checked for viruses by Avast antivirus software. > > > https://www.avast.com/antivirus > > > > > > > > > > > > > > > > > --- > > This email has been checked for viruses by Avast antivirus software. > > https://www.avast.com/antivirus > > > > > > > ---------------------------------------------------------------------------- > -- > > _______________________________________________ > > Nfs-ganesha-devel mailing list > > Nfs-ganesha-devel@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/nfs-ganesha-devel > > > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus > > > --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ------------------------------------------------------------------------------ _______________________________________________ Nfs-ganesha-devel mailing list Nfs-ganesha-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs-ganesha-devel
