If you run a 'find /<full-path-to-brick>' would probably take a lot of time. Now imagine that gluster also has to check the extended attributes of each file/dir and it becomes quite slow. Also , we do not know anything of the following: - HDDs IOPS rating - mount options for the bricks - I/O scheduler for your HDDs and DM devices - is selinux enabled - Network bandwidth - Load on the 2 servers before and after the heal has been started - Volume settings I would expect that gluster heal is with lower ionice than regular read/write operations coming from the clients - nobody wants a cluster dead due to a healing operation ongoing.Also , check the logs on all nodes for any errors during the healing - maybe you got some issues that were not noticed before. Best Regards, Strahil Nikolov В петък, 11 септември 2020 г., 12:13:06 Гринуич+3, Martin Bähr <mbaehr+gluster@xxxxxxxxxx> написа: Excerpts from Gionatan Danti's message of 2020-09-11 08:34:04 +0200: > > we have a 3-node replica cluster running version 3.12.9 > > with 32TiB of space. each node has a single brick on > > top of a 7-disk raid5 (linux softraid) > 3.12.9, while being the official RHEL 7 release, is very old now. yes, i am aware. we didn't bother upgrading as we need to expand capacity and it's cheaper to rent new servers than expand the old ones. > > the accumulated changes of one month of operation took 4 months to > > heal. > Wow, 4 months is a lot... but you had at least internal redundancy > (RAID5 bricks). right, that, and we had 3 replicas. we could have just dropped the third node, and would still have been ok. for the new cluster we decided that 2 nodes is enough, because the data is all backups anyways. even if we loose both nodes, we can at least in theory still recover all the data. whether that's a good decision is a risk calculation. is a third server worth the extra expense? we decided that, for what is essentially a backup, it's not. i considered 3 nodes but dropping the raid instead, but several comments inclusing yours convinced me that keeping the raid is good. on the new servers we'll each have 3 bricks with 5 disks in a raid 5 per brick. > > the initial heal count was about 6million files for one node and > > 5.4million for the other. > > ... > > we do have a few huge directories with 250000, 88000, 60000 and 29000 > > subdirectories each. in total 26TiB of small files, but no more than > > a few 1000 per directory. (it's user data, some have more, some have > > less) > > > > could those huge directories be responsible for the slow healing? > > The very high number of to-be-healed files surely has a negative impact > on your heal speed. that sounds like that there is an inefficiency within the healing process that causes the healing speed to be non-linear depending on the number of files. greetings, martin. -- general manager realss.com student mentor fossasia.org community mentor blug.sh beijinglug.club pike programmer pike.lysator.liu.se caudium.net societyserver.org Martin Bähr working in china http://societyserver.org/mbaehr/ ________ Community Meeting Calendar: Schedule - Every 2nd and 4th Tuesday at 14:30 IST / 09:00 UTC Bridge: https://bluejeans.com/441850968 Gluster-users mailing list Gluster-users@xxxxxxxxxxx https://lists.gluster.org/mailman/listinfo/gluster-users ________ Community Meeting Calendar: Schedule - Every 2nd and 4th Tuesday at 14:30 IST / 09:00 UTC Bridge: https://bluejeans.com/441850968 Gluster-users mailing list Gluster-users@xxxxxxxxxxx https://lists.gluster.org/mailman/listinfo/gluster-users
