Affects Version/s: Lustre 2.7.0, Lustre 2.10.0
We have blocked new object creation to some of our OSTs with commands like:
lctl set_param osp.$OSTNAME.max_create_count=0
This is to drain data off of storage to be repurposed as spares. Three targets are already at 0%, and confirmed to have no remaining objects with e2scan and lester. 11 other targets are blocked and data is being migrated off.
Noticed that a few of the other targets were filling up, while others had plenty of space. Watching it over a few days and the imbalance is getting worse.
Confirmed that we are using default allocation settings:
nbp7-mds1 ~ # lctl get_param lov.*.qos_*
Tests creating 100k new files of stripe count 1 showed that the more full OSTs are indeed getting allocated objects more often.
This looks like it might be similar to