Hi Maynor,  MirrorView/A uses snapshots to make a golden copy of the data during synchronization. This causes the COFW (Copy On First Write) proces to start which generates a delay and traffic to your RLP.  If your RLP is undersized, this will limit performance of your complete mirror while it is synching. Also, regardless of IOps, the COFW will always introduce some extra latency so even in a perfectly sized environment you're bound to see a couple of extra milliseconds of latency.
steps  done:  migrate source metalun to metalun wich has 3 components in 3 FC RG. destroy and recreate mirror re-create reserved lun pool in FC disks  and results seens to be the same.  the host accessing this meta is a vmware virtual machine wich is in a hardware host conected to primary SAN in FC. and the metalun is presented as a RDM disk.   does any one has idea where the bootleneck is, and why mirrorview/a when active slows donws the i/o and response of the host.  thank you  MC.
2 x cx3-10c after recreate async mirror and RLPs, why when mirror is active 
host gets slow