I've been doing some benchmarking recently to satisfy the curiosity about 5.1's performance compared with 4.1. The major question this time revolves around how much additional performance an external RAID array can provide (for us it's typically beyond the 6 drives a Dell 2950 can hold).
These tests are done on using an MSA-30 drive enclosure with 15k-SCSI drives. The testing framework is sysbench oltp. The test names are hopefully fairly obvious: selects = single selects, reads = range tests, xacts = transaction tests, etc. Transaction tests are counting individual queries, not transactions. The "Rdm" tests are using a uniform distribution, whereas the non-'Rdm' tests are 75% of queries are using 10% of the rows.
