Performance on AIX

Hi all,

At Bull company, we want to answer a call for tender from a large
company. And we are asked for information about PostgreSQL performance
under AIX on Power 7 servers.

By chance, has someone some data about this ?
Has someone performed a benchmark using AIX quite recently ?

Are there any reasons for having performance level significantly
different between AIX and, let say, Linux, on a given platform ?

Thanks by advance for any help.

Philippe BEAUDOIN