7.8. Disabling Inter-Tier Data Allocation

If a storage tier runs out of free space, Virtuozzo Storage will attempt to temporarily use the space of the lower tiers down to the lowest. If the lowest tier also becomes full, Virtuozzo Storage will attempt to use a higher one. If you add more storage to the original tier later, the data, temporarily stored elsewhere, will be moved to the tier where it should have been stored originally.

Mixing tier workloads is not recommended as it may decrease cluster performance. To prevent this, you can disable automatic data migration between tiers after making sure that each tier have enough free space. Execute the following command on any cluster node:

# vstorage -c cluster1 set-config mds.alloc.strict_tier=1