From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olaf Weber Date: Wed, 16 Sep 2015 18:14:13 +0200 Subject: [lustre-devel] adding IOCTL for ping In-Reply-To: References: <55F88186.50803@llnl.gov> Message-ID: <55F99555.4020900@sgi.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org On 16-09-15 17:24, Patrick Farrell wrote: > A further thought: wouldn't an ioctl be unusable on servers? Presumably it would use the /dev/lnet device file, like the other ioctls in libcfs/include/libcfs/libcfs_ioctl.h. Olaf > ________________________________________ > From: Simmons, James A. [simmonsja at ornl.gov] > Sent: Wednesday, September 16, 2015 10:16 AM > To: Ben Evans; Patrick Farrell; Christopher J. Morrone; lustre-devel at lists.lustre.org > Subject: RE: [lustre-devel] adding IOCTL for ping > >> My understanding is that adding new proc interfaces is discouraged by >> upstream linux. > > Please no new ioctls. > > On 9/15/15, 5:12 PM, "Patrick Farrell" wrote: > >> Hmmm. What about a proc interface instead? This feels - to me - better >> suited to that, since it's a control that isn't part of the I/O path in >> any way. >> ________________________________________ >> From: lustre-devel [lustre-devel-bounces at lists.lustre.org] on behalf of >> Ben Evans [bevans at cray.com] >> Sent: Tuesday, September 15, 2015 3:53 PM >> To: Christopher J. Morrone; lustre-devel at lists.lustre.org >> Subject: Re: [lustre-devel] adding IOCTL for ping >> >> You?re correct, targets and client Ids would probably be better. I was >> simply thinking that it would be a relatively straightforward piece of >> code to write that could add some good flexibility into Lustre. Combine >> it with an "X is dead, evict it? IOCTL and you could probably do quite a >> bit of good, especially if you?ve got a management system that is also >> monitoring aliveness, locations of targets, etc. >> >> -Ben Evans >> >> On 9/15/15, 4:37 PM, "lustre-devel on behalf of Christopher J. Morrone" >> >> wrote: >> >>> Maybe there is just not enough detail in the proposal, but I am not >>> seeing why associating this with NIDs is the right way to go. I believe >>> that the RAS work that would use the gossip protocol dealt, at least in >>> part, with higher level concepts like targets. The existing ptlrpc >>> pinger pings targets, not NIDs. That is one of the problematic design >>> points of the existing system, that when N OSTs live on the same node >>> clients need to send N pings to the same node. >>> >>> Chris >>> >>> On 09/15/2015 08:04 AM, Ben Evans wrote: >>>> Would there be any interest in adding an IOCTL to update the ping >>>> time/status for a particular NID? >>>> >>>> This should allow for implementation of a pinger in userspace which >>>> updates the kernel on the status of various NIDs, and if I understand >>>> the ping code well enough, would greatly curtail any pings that is sent >>>> by the kernel. >>>> >>>> This might allow for things like Eric?s gossip implementation to simply >>>> bolt on top of Lustre without any internal kernel changes, or for >>>> integration of external monitoring systems to tell Lustre that >>>> failovers >>>> have occurred, etc. >>>> >>>> -Ben Evans >>>> >>>> >>>> _______________________________________________ >>>> lustre-devel mailing list >>>> lustre-devel at lists.lustre.org >>>> http://lists.lustre.org/listinfo.cgi/lustre-devel-lustre.org >>>> >>> >>> _______________________________________________ >>> lustre-devel mailing list >>> lustre-devel at lists.lustre.org >>> http://lists.lustre.org/listinfo.cgi/lustre-devel-lustre.org >> >> _______________________________________________ >> lustre-devel mailing list >> lustre-devel at lists.lustre.org >> http://lists.lustre.org/listinfo.cgi/lustre-devel-lustre.org > > _______________________________________________ > lustre-devel mailing list > lustre-devel at lists.lustre.org > http://lists.lustre.org/listinfo.cgi/lustre-devel-lustre.org > _______________________________________________ > lustre-devel mailing list > lustre-devel at lists.lustre.org > http://lists.lustre.org/listinfo.cgi/lustre-devel-lustre.org > -- Olaf Weber SGI Phone: +31(0)30-6696796 Veldzigt 2b Fax: +31(0)30-6696799 Sr Software Engineer 3454 PW de Meern Vnet: 955-6796 Storage Software The Netherlands Email: olaf at sgi.com