With the described embodiments, the target server automatically determines to release space after forming the consistency group to automatically release space at the target volume to be available for use in other thin provisioned volume. Since the target server has the current information on the state of the target volume, the target server may more efficiently determine to release space than a host system or operator at the host system.

FIG. 1 illustrates an embodiment of a data storage environment having at least two storage systems 100₁ and 100₂, each including storage servers 200₁ and 200₂, respectively, managing access to volumes 104₁ and 104₂ configured in storages 106₁ and 106₂. Host systems (not shown) may perform read and write operations with respect to the first storage system 100₁ over a storage network 110. A source storage 106₁ may comprise a primary production volume to which hosts direct read and write request. The source server 200₁ may mirror tracks in the source volumes 104₁ to the target storage system 100₂ to maintain data in consistency groups at the target server 200₂. A track may comprise any data unit type, such as a track, logical block, extent, page, etc.

When formation of the tracks for a consistency group is completed in the target volume 104₂, the target server 200₂ may create a point-in-time copy 108 of the target volume 104₂ for the consistency group. There may be multiple point-in-time copies at different consistency group times for a target volume 104₂.