UIM/P is the management application used to provision new storage to VCE vBlock system. For vBlock 700 series, UIM/P by default creates TDEVs with no prea-llocation set. However, it is so easy to override this behavior. Some customers may like to have the devices pre-allocated for performance reasons. However, this is absolutely not recommended when enabling FAST VP on the array.
So starting with how to change the preallocation size. You should login yo UIM/P with root credentials. then cd to the below directory:
/opt/ionix-uim/package/pkgxml/EMCSymmetrixCLI and then open file Luntypes.xml
This file has very useful example there on how to change the default LUN type, so to add my new SYMM array I added the below lines:
So for array SN# 00029871616, UIM/P will provision TDEVs fully preallocated for devices created from pool T1_FC_R5, T1_FC_R1, T1_SATA_R6 while all TDEVs created from any other pool will not be preallocated. To double check the created devices, check symapi logs from the SE server you will see it looks like this: