HP-UX Encrypted Volume and File System Performance and Tuning

EVFS Encryption Key Length
EVFS can be configured for different symmetric encryption keys lengths. The default key length is AES
128 bit. Some institutions require stronger encryption, so EVFS also provides AES 256 bit keys. The
following test illustrates how EVFS performs when using 128 bit versus 256 bit encryption keys.
Figure 26: Random Writes, 128 and 256 AES Keys
This test was performed using random writes, default VxFS tuning, and buffer cache at 5-50%. EVFS
throughput and CPU utilization are effectively unaffected by the encryption key length – the results are
almost identical.
Figure 27: Sequential Reads, 128 and 256 AES Keys
64k Block Random Write - 100mb File Size
3%
15%
20%
25%
25%
4%
15%
21%
25%
28%
1 10 25 50 100
IOZone Threads
CPU Utilization %
Throughput KBs -
Scale20
AES128 CPU AES256 CPU
AES128 Random Write AES256 Random Write
64k Block Sequential Read - 100mb File Size
8%
19%
24%
27%
26%
12%
18%
25%
26%
27%
1
IOZone Threads
CPU Utilization %
Throughput KBs -
Scale1
AES128 CPU AES256 CPU AES128 read AES256 read