You can tell that something is wrong when:
- Something that usually takes half an hour is not finished after 5 hours OR
- Yet another piece of technology is functioning in unintended ways.
A couple of days ago I read a tip about 4 mistakes that can kill VM performance.
#4 was: The default power option of Windows Server 2008 upon installation is set to "Balanced".
Sure as hell it was set to Balanced, so I corrected that one.
But tonight something else happened that was related to power management.
A backup to network folder was taking far too long.
How nice... One more problem to solve...
I check the network utilization and see that it was 100%.
Now that's a bit unusual... Just a bit...
I take a better look and what do I see?
Link Speed 10Mbps!!!!!
Excuse me??? Where did that come from?
To cut a long story short, the Intel network adapters came with a default setting that made them reduce the link speed if the machine is idle. The machine was certainly not idle, but still the link speed was reduced... go figure.
I deactivated the setting and got back my 1Gbps with a healthy 30% utilization and my backup was finished in the next 10 minutes.
That's why I say too much power management will kill you...