Le 2021-06-22 20:21, Gilles Mocellin a écrit :
Hello Cephers,
On a capacitive Ceph cluster (13 nodes, 130 OSDs 8To HDD), I'm migrating a 40 To image from a 3+2 EC pool to a 8+2 one.
The use case is Veeam backup on XFS filesystems, mounted via KRBD.
Backups are running, and I can see 200MB/s Throughput.
But my migration (rbd migrate prepare / execute) is staling at 4% for 6h now.
When the backups are not running, I can see a little 20MB/s of throughput, certainly my migration.
I need a month to migrate 40 TB at that speed !
Hello, It seems worst, this morning, I still see a 4% completed status. The metrics I can see other the last 12h are not showing much activity... So it seems more stale than slow. Is anyone using that rbd migration command, on reasonable sized image ? And of course between different data pools ? During my initial tests, it worked, but with little and quite empty test images (1 TB)... I will investigate an alternate method, like : - snapshot src image - copy src image to new data pool (new image name) - unmount src image - export-diff | import-diff delta from src image with snap to dest image - test mount dest image - delete src image - rename dest image The unknown duration here is for the export/import diffs. But during the initial copy, my production can continue. Anyon has already done something similar and can comment on the duration, or pinpoints ? -- Gilles