Naturally the best benchmark is your own workload. Any canned benchmark will be different than the live workload you witness on your particular system. Still for kicking the tires on a new DBMS installation, for exploring tuning impacts of various variables in general etc. canned benchmarks can be marvelous.
HammerDB appears to be just the ticket. It supports TPC-C and TPC-H against SQLServer, MySql, Oracle, Greenplum, Postgres and Redis. It runs on windows and linux.
Check it out at the above link.