What are the performance considerations of using dual logging
(MIRRORLOGPATH) in DB2 LUW on a Hitachi SAN. I am fairly sure that the
overhead is minimal, but I am interested in knowing the exact details, and
whether the both the primary log and MIRRORLOGPATH are written synchronously
with the COMMIT, or whether the only the write of the primary log is
synchronous with the COMMIT.

In my case, the MIRRORLOGPATH would be located on a slightly slower disk
than the primary log.