On Jun 24, 2008 17:35 -0700, Huang, Eric wrote: > Got another question, does Lustre provide a different user level library > to access the file system? I mean, when the user application does a > "read" or "write", is it using the regular Linux library to conduct > these system calls? Or does Lustre provide its own, such that these > "read" and "write" calls are not typical VFS calls anymore? My > understanding is that Lustre has its own user-level library that > intercepts these system calls and send commands across Lnet to get/write > data. Only the meta-data related calls (such as INODE allocation, > deletion, etc.) are actually passed to VFS. Am I right?
No, Lustre is a regular filesystem that is POSIX compliant. There IS a userspace Library for Lustre, but that is used only for a very limited class of systems, normally the Catamount clients on the Cray XT3, and if non-Linux clients are using FUSE to access Lustre (e.g. OSX, FreeBSD). > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf > Of Andreas Dilger > Sent: Monday, June 23, 2008 3:56 PM > To: Huang, Eric > Cc: [EMAIL PROTECTED] > Subject: Re: [Lustre-discuss] Lustre and memory-mapped I/O > > On Jun 19, 2008 10:18 -0700, Huang, Eric wrote: > > Here is the error: > > > > *** USER FATAL MESSAGE 1250 (BIOCRT) > > STATUS = 38, FILX = 3, LOGNAME = MASTER , NSBUF3 = > > 65536 > > FILE = /lustre/client/4way/xx0cmd0.T18856_24.t7.MASTER > > ERROR MESSAGE IS -- > > Function not implemented (errno = 38) > > *** SYSTEM FATAL MESSAGE 446 (DBCRT) > > ERROR ATTEMPTING TO CREATE A FILE (LOGICAL= MASTER ) FOR DBSET > > MASTER WITH READ AND WRITE PRIVILEGES. > > USER ACTION: CHECK THE AVAILABLE/ALLOCATED SPACE AND THE > PRIVILEGES > > GRANTED THIS ACCOUNT. > > > > USER INFORMATION: THIS ERROR OCCURS WHEN MORE THAN ONE JOB HAS > WRITE > > PRIVILEGE AT THE SAME TIME. > > ONLY ONE JOB CAN HAVE WRITE PRIVILEGE. > > 0FATAL ERROR > > 1 * * * END OF JOB * * * > > > > > > I think it may have to do with the Lustre lock implementation. The > > directory /lustre/client/4way is a directory with file-striping set to > 4. > > Is this application trying to use flock? Then the client needs to > be mounted with flock support, either "-o flock" to enable distributed > flock (lower performance), or "-o localflock" (for local node flock > only, > if application only needs flock on a single node). > > Cheers, Andreas > -- > Andreas Dilger > Sr. Staff Engineer, Lustre Group > Sun Microsystems of Canada, Inc. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. _______________________________________________ Lustre-discuss mailing list Lustre-discuss@lists.lustre.org http://lists.lustre.org/mailman/listinfo/lustre-discuss