Backup Encryption Overhead
Hi
We are testing backup encription using BUE 2012 3600 appliance and are noticing some significant overheads of the encryption.
Can anyone advise it there and any published statistics of what overhead is realisitc.
Applaince is:
Windows 2008 Server
BUE 2012 with SP2 installed
4 CPU
16GB RAM
4 x 1GB NIC but with only 1 in use
Attached HP MSL 2024 tape library SAS attached
Out test results to local appliance disk are as below:
Job type – D2D |
Time mins |
Throughput mps |
%Overhead Non encrypted or compressed |
Encrypted – Software compression – 25gb – small files – disk1 |
28.21 |
1,225,00 |
+45.8 |
Encrypted – No compression – 25gb – small files – disk1 |
21.51 |
1,677,00 |
+6.16 |
Not Encrypted – Software compression – 25gb – small files – disk1 |
19.35 |
1,733,00 |
3 |
Not Encrypted – No compression – 25gb – small files – disk1 |
18.23 |
1.786,00 |
|
Job type – Duplicate to tape |
Time mins |
Throughput mps |
%Overhead Non encrypted or compressed |
Encrypted – Software compression |
57.47 |
894 |
+255 |
Encrypted – No compression |
38 |
916 |
+248 |
Not Encrypted – Software compression |
44 |
1,495,00 |
+35 |
Not Encrypted – No compression |
18.55 |
2,283,00 |
|
Any thoughts or documentation (other than admin guide) would be appriciated
When you encrypt your backups, there is definitely overheads and it can be significant. This is why you should use encryption sparingly. I only encrypt the backups that goes off-site.
You should always use either software encryption and software compression or hardware encryption and hardware compression. Do not mix software encryption with hardware compression or hardware encryption with software compression. If you are using LTO4 tapes, then you can use hardware encryption and hardware compression when you backup to tapes.
If you are backing up to the appliance internal harddisk which is a dedup folder, then you should not use any encryption or compression as these dedup badly.