RAID rebuild causing very high M3 paging

unknown

We are running M3 13.1 and 13.2 on IBM iSeries connected to IDB V7000 SAN.
A failed disk was replaced on the SAN resulting in a RAID5 rebuild (There are 6 raid 5 sets on the SAN).
At the very same time the raid started to rebuild M3 because unusable and after further investigation it was notice that the bootstrap for one of the environments started doing a large amount of paging causing very high I/O back to the SAN.
Has anyone experienced this type of issue before.