Hi Rob, I can answer for Cengiz. Pete Wyckoff and the OSC folk had done some work getting PVFS to work with OSD. That was with PVFS 2.7.1. We are trying to bring it up to date with 2.8.4. Since OSDs do not have precreate support, we need a way to disable that functionality. It looks like we are going to have dig into the state machines and follow Michael's suggestions.
John. On Jun 2, 2011, at 10:56 AM, Rob Ross wrote: > Hi, > > In short Cengiz, you're going to have to do a little work if you want to turn > off the precreate functionality and go back to the old way of allocating > metadata and data objects. That code isn't being tested or supported any > more; the new way of doing things is simply better for most users. Another > option would be to use an older version of PVFS that does not have this > feature. > > Rob > > On Jun 2, 2011, at 9:51 AM, Michael Moore wrote: > >> I checked a little closer in the create state machine. If I'm reading it >> correctly, the only way to only get local file handles it to have the >> stuffed option on. Otherwise, remote file handles will be allocated and the >> only way those currently get populated is from precreate pools. Of course >> testing the configuration is the only definitive way to know where and if it >> breaks. >> >> To change the reliance on precreate behavior my thought would be to change >> the state machines that rely on job_precreate_pool_get_handles() to have a >> different way to get handles. In other words, based on some flag have the >> state machine take one of two paths 1) get handles normally with precreate >> 2) the old route. Now, I am not familiar with the 'old route' so I don't >> know how well it would fit. >> >> Michael >> >> On Thu, Jun 2, 2011 at 8:39 AM, Phil Carns <[email protected]> wrote: >> I share Michael's curiosity as well, but I think it might be possible to >> disable the precreate functionality using config file options if you really >> need to (not recommended): >> >> Set the FileStuffing option to "no" to prevent the file system from using >> the file stuffing optimization that relies on precreated objects: >> >> http://www.pvfs.org/cvs/pvfs-2-8-branch-docs/doc//pvfs-config-options.php#FileStuffing >> >> And then also set the PrecreateLowThreshold to 0 to prevent the servers from >> trying to fill up their respective pools of precreated objects on startup: >> >> http://www.pvfs.org/cvs/pvfs-2-8-branch-docs/doc//pvfs-config-options.php#PrecreateLowThreshold >> >> I have never tried that particular configuration so I can't say for sure if >> it will work or not. >> >> -Phil >> >> >> On 06/01/2011 09:52 PM, Michael Moore wrote: >>> >>> Hi Cengiz, >>> >>> I'm curious, what's the use case for needing the precreate functionality >>> disabled? Migration from an older version? >>> >>> Thanks, >>> Michael >>> >>> On Wed, Jun 1, 2011 at 3:01 PM, Karakoyunlu, Cengiz >>> <[email protected]> wrote: >>> Is it possible to disable the precreate functions in orangefs-2.8.4 and use >>> the traditional methods existed in previous distributions to start server, >>> perform i/o operations etc.? >>> >>> Thank you, >>> >>> Cengiz >>> >>> _______________________________________________ >>> Pvfs2-developers mailing list >>> [email protected] >>> http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers >>> >>> >>> >>> _______________________________________________ >>> Pvfs2-developers mailing list >>> [email protected] >>> http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers >> >> >> _______________________________________________ >> Pvfs2-developers mailing list >> [email protected] >> http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers >> >> >> _______________________________________________ >> Pvfs2-developers mailing list >> [email protected] >> http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers > > _______________________________________________ > Pvfs2-developers mailing list > [email protected] > http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers _______________________________________________ Pvfs2-developers mailing list [email protected] http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers
