10.1 的信息中心里面说了一个类似的例子
Increasing the size of device containers. The following exampleillustrates how to increase two device containers (each already existingwith 1 000 pages) in a table space on a Linux or UNIX operating system:
[code class=\"\"] ALTER TABLESPACE HISTORYThe twodevices increase from 1 000 pages in size to 2 000 pages.The contents of the table space might be rebalanced across the containers. Access to the table space is not restricted during the rebalancing.
里面说到了 resize 也是有可能触发 rebalancing , 可能是因为当前数据在各个 containers 之间分布不均匀,达到了一个内部的阈值,从而触发了 rebalancing 的操作,如果想知道进一步的细节,可能需要开 PMR 问下 lab 的 db2 support team