HP-UX Encrypted Volume and File System Performance and Tuning

configured at 5-50% by default - utilizing 3.4GB at startup. Observe “Sys Mem” and “Buf Cache” on

the bottom lines of the display.

Figure 4 - System Memory at Startup

Using IOZone (see the Testing Methodology chapter for details) to drive the system to maximum data

transfer capacity to a storage device configured for non-EVFS data, system memory (Sys Mem)

utilization is increased to 6.6GB maximum, and buffer cache (Buf Cache) is peaked at the configured

upper threshold of 50%, or 32GB. So a clear-data transfer utilizes 3GB of system memory (6.6GB –

3.6GB).

Figure 5 - System Memory After Clear I/O Copy

Running the same test on the same system (after a reboot to reinitialize all system variables) except the

data is written to a configured EVFS file system, shows that system memory (Sys Mem) is driven to

7.1GB, while buffer cache (Buf Cache) remains limited to the 32GB threshold.