Some tests showed that using 70% or 80% of the disk capacity can show the realistic performance characteristic. The achieved IO is up to 100% more than what you can really get when 80% of the disk is utilized in terms of its capacity. Refer to a TechNet...

JetStress (WR 1.2: 06.05.7529.0) --- Calculation is like the following: Planned Data: 750 users * 200 MB = 150 GB. Initial Data: 150 GB * 75% = 112.5 GB. Initial EDB: 112.5 GB * 1.67% = approximately 188 GB --- 112.5 GB mailbox data + 66%...

JetStress (WR2.1) uses Database Page Fault Stalls Per Sec instead of Database disk write latency. It's mainly because it could handle SRDF/sync environment. In SRDF/sync environment, database disk write latency can go over 20 ms on average, but it...