At our university many of our students and professors use SQLite and Berkley DB for their projects. Probally, BDB more than SQLite. Would I we need to have Lustre mounted up a certain way to avoid corruption via file locking? Any thoughts about this? TIA
On Jan 16, 2009 00:52 -0500, Mag Gam wrote:> At our university many of our students and professors use SQLite and > Berkley DB for their projects. Probally, BDB more than SQLite. Would I > we need to have Lustre mounted up a certain way to avoid corruption > via file locking? Any thoughts about this?That depends on how they use it. Mounting Lustre with "-o localflock" will provide locking on a single node without any performance impact, which is enough for single-node databases like SQLite and Berkley DB. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc.
Thanks Andreas. We also run Sun Grid Engine for our engineering department. Out setup is basically like this: Master -- QMASTER (1 server) Slaves -- EXECD (300 servers) They are share a filesystem which is running of Lustre. Grid Engine has a Berkeley Database as its backend. I am wondering if I need to change all of my slaves and master to distributed locking or local locking. Any thoughts? TIA On Fri, Jan 16, 2009 at 10:10 AM, Andreas Dilger <adilger at sun.com> wrote:> On Jan 16, 2009 00:52 -0500, Mag Gam wrote: >> At our university many of our students and professors use SQLite and >> Berkley DB for their projects. Probally, BDB more than SQLite. Would I >> we need to have Lustre mounted up a certain way to avoid corruption >> via file locking? Any thoughts about this? > > That depends on how they use it. Mounting Lustre with "-o localflock" > will provide locking on a single node without any performance impact, > which is enough for single-node databases like SQLite and Berkley DB. > > Cheers, Andreas > -- > Andreas Dilger > Sr. Staff Engineer, Lustre Group > Sun Microsystems of Canada, Inc. > >
Hi Mag, If I''m not mistaken, only qmaster writes to the DB, the execd process relays queries through a listening daemon using RPC on the qmaster host which speaks BDB on the back end. hth, Klaus On 1/16/09 4:22 PM, "Mag Gam" <magawake at gmail.com> etched on stone tablets:> Thanks Andreas. > > We also run Sun Grid Engine for our engineering department. Out setup > is basically like this: > > Master -- QMASTER (1 server) > Slaves -- EXECD (300 servers) > > > They are share a filesystem which is running of Lustre. Grid Engine > has a Berkeley Database as its backend. I am wondering if I need to > change all of my slaves and master to distributed locking or local > locking. > > Any thoughts? > > TIA > > On Fri, Jan 16, 2009 at 10:10 AM, Andreas Dilger <adilger at sun.com> wrote: >> On Jan 16, 2009 00:52 -0500, Mag Gam wrote: >>> At our university many of our students and professors use SQLite and >>> Berkley DB for their projects. Probally, BDB more than SQLite. Would I >>> we need to have Lustre mounted up a certain way to avoid corruption >>> via file locking? Any thoughts about this? >> >> That depends on how they use it. Mounting Lustre with "-o localflock" >> will provide locking on a single node without any performance impact, >> which is enough for single-node databases like SQLite and Berkley DB. >> >> Cheers, Andreas >> -- >> Andreas Dilger >> Sr. Staff Engineer, Lustre Group >> Sun Microsystems of Canada, Inc. >> >> > _______________________________________________ > Lustre-discuss mailing list > Lustre-discuss at lists.lustre.org > http://lists.lustre.org/mailman/listinfo/lustre-discuss
Klaus: You are correct. So, I suppose I need the local lock on my qmaster node? Is that correct? TIA On Fri, Jan 16, 2009 at 11:03 PM, Klaus Steden <klaus.steden at technicolor.com> wrote:> > Hi Mag, > > If I''m not mistaken, only qmaster writes to the DB, the execd process relays > queries through a listening daemon using RPC on the qmaster host which > speaks BDB on the back end. > > hth, > Klaus > > On 1/16/09 4:22 PM, "Mag Gam" <magawake at gmail.com> etched on stone tablets: > >> Thanks Andreas. >> >> We also run Sun Grid Engine for our engineering department. Out setup >> is basically like this: >> >> Master -- QMASTER (1 server) >> Slaves -- EXECD (300 servers) >> >> >> They are share a filesystem which is running of Lustre. Grid Engine >> has a Berkeley Database as its backend. I am wondering if I need to >> change all of my slaves and master to distributed locking or local >> locking. >> >> Any thoughts? >> >> TIA >> >> On Fri, Jan 16, 2009 at 10:10 AM, Andreas Dilger <adilger at sun.com> wrote: >>> On Jan 16, 2009 00:52 -0500, Mag Gam wrote: >>>> At our university many of our students and professors use SQLite and >>>> Berkley DB for their projects. Probally, BDB more than SQLite. Would I >>>> we need to have Lustre mounted up a certain way to avoid corruption >>>> via file locking? Any thoughts about this? >>> >>> That depends on how they use it. Mounting Lustre with "-o localflock" >>> will provide locking on a single node without any performance impact, >>> which is enough for single-node databases like SQLite and Berkley DB. >>> >>> Cheers, Andreas >>> -- >>> Andreas Dilger >>> Sr. Staff Engineer, Lustre Group >>> Sun Microsystems of Canada, Inc. >>> >>> >> _______________________________________________ >> Lustre-discuss mailing list >> Lustre-discuss at lists.lustre.org >> http://lists.lustre.org/mailman/listinfo/lustre-discuss > >