The underlying MDT filesystem is actually ZFS and not ldiskfs, but it should be equally possible to expand the MDT storage capacity by adding another mirrored VDEV to the MDT pool.
It is also important to ask if there are any snapshots of the pool? That would also hold space in the pool even if the files are deleted. That said, there wasn't enough information to determine if there is actually a problem with the filesystem or if it is just full. Just because the MDT did not fill up previously, is no indication that the MDT will not fill up if the average file size is smaller this time around. What does "lfs df -i" and "lfs df" report for filesystem? That would allow figuring out how much space is used on the MDT and how many files in the filesystem, and the average space used per file on the MDT. It should be in the 2-3KB or less range. Cheers, Andreas On Jun 10, 2014, at 6:14, "E.S. Rosenberg" <esr+lus...@mail.hebrew.edu<mailto:esr+lus...@mail.hebrew.edu>> wrote: Did anyone answer this? >From my way too basic understanding should it be possible to expand an MDT? >after all the underlying fs is ext4? On Mon, Jun 2, 2014 at 5:12 PM, Anjana Kar <k...@psc.edu<mailto:k...@psc.edu>> wrote: The MGS/MDT pool and filesystem were created using these commands: zpool create -f -o ashift=12 -O canmount=off lustre-mgs-mdt mirror /dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 /dev/disk/by-path/pci-0000: 00:1f.2-scsi-1:0:0:0 mkfs.lustre --mgs --mdt --fsname=iconfs --backfstype=zfs --dev ice-size 131072 --index=0 lustre-mgs-mdt/mgsmdt0 However, now the MDT is full, and 8 OSTs are 86% full. lustre-mgs-mdt/mgsmdt0 73G 73G 0 100% /mnt/lustre/local/mgsmdt lustre-ost0/ost0 13T 11T 1.8T 86% /mnt/lustre/local/ost0 Is there a way to clear space, or will the filesystem/MDT need rebuilt? Previously, the same disks were used for creating a mirrored MDT w/o -ashift=12, and did not fill up even when the OSTs were at 89%. Thanks for any advice. -Anjana Kar Pittsburgh Supercomputing Center k...@psc.edu<mailto:k...@psc.edu> _______________________________________________ Lustre-discuss mailing list Lustre-discuss@lists.lustre.org<mailto:Lustre-discuss@lists.lustre.org> http://lists.lustre.org/mailman/listinfo/lustre-discuss _______________________________________________ Lustre-discuss mailing list Lustre-discuss@lists.lustre.org<mailto:Lustre-discuss@lists.lustre.org> http://lists.lustre.org/mailman/listinfo/lustre-discuss _______________________________________________ Lustre-discuss mailing list Lustre-discuss@lists.lustre.org http://lists.lustre.org/mailman/listinfo/lustre-discuss
