In the Huawei storage system using RAID2.

Resolution: A LUN can be created as a Thick LUN and Thin LUN. Thick LUN will be allocated from the storage pool in advance

Storage capacity, even if no user data is stored on the Thick LUN. Thin LUNs are not pre-allocated from the storage pool

For storage capacity, only when user data is written to the thin LUN will the actual storage capacity be allocated from the storage pool.

Sequential read: Since thin LUN dynamically allocates storage resources according to the actual needs of users, space allocation exists in time

Discontinuity, so it will affect the continuity of the space mapped on the disk. When thick LUN is created, the system

Automatic resource allocation technology allocates storage resources from storage resources at one time, which maximizes its mapping to

Space continuity on the disk. Sequential reading of mechanical disks is more efficient, so thick LUNs perform better when reading sequentially

For thin LUN.