keboose
Explorer
- Joined
- Mar 5, 2016
- Messages
- 92
I currently have a setup with four AMD Opteron 6128 processors, and twelve 1TB WD Red hard drives. I have such a processor setup for a few reasons: I planned for multiple Plex transcodes (at least 4 1080P streams,) They encode videos with Handbrake WAY faster than my personal PC, and I got a really good deal (about $300 for the board, all four processors, and some RAM.)
I recently started logging my power usage using the features on my APC UPS, and found that the server is using more than double the amount of electricity I predicted when I first built it, and totals nearly 30 USD per month in electricity. According to the data, my server idles around 260 watts the majority of the time. I did my best to minimize drive usage (moved my data collection from my NAS share to a folder on my boot drives,) but the Plex and owncloud plugins I have running seem to keep the drives on pretty much all the time.
This has prompted me to upgrade to a newer processor. Just going to a new generation alone would cut my power usage significantly, since two lower-end xeon processors would have an equivalent processing power to all four Opterons. I do have a question, though, about how low I can go when idling. Modern processors seem to have several power saving features, namely "states" (p-states and c-states) that allow the processor to downclock or disable cores when they are not being used. I'll admit I don't fully understand what they do, only that they are advertised as reducing power consumption.
My main question is, with FreeNas, would I be able to utilize these features? It's my understanding that whatever "p-states" are, are intel-specific hardware-set states that I can't change myself, and "c-states" are core-specific states that can be set by commands from the BIOS/OS. is that correct? Would I be able to change the c-state of several cores to shut some down when I am away? Are there other power saving features I could utilize besides states? If I were to change c-states on my Opterons, would that have any effect on power usage? Right now, if I query the system for c-state ability, I get this response for every core:
I'm not sure how to interpret these lines. Could I change anything to shut down some cores while I shop for a new system?
I recently started logging my power usage using the features on my APC UPS, and found that the server is using more than double the amount of electricity I predicted when I first built it, and totals nearly 30 USD per month in electricity. According to the data, my server idles around 260 watts the majority of the time. I did my best to minimize drive usage (moved my data collection from my NAS share to a folder on my boot drives,) but the Plex and owncloud plugins I have running seem to keep the drives on pretty much all the time.
This has prompted me to upgrade to a newer processor. Just going to a new generation alone would cut my power usage significantly, since two lower-end xeon processors would have an equivalent processing power to all four Opterons. I do have a question, though, about how low I can go when idling. Modern processors seem to have several power saving features, namely "states" (p-states and c-states) that allow the processor to downclock or disable cores when they are not being used. I'll admit I don't fully understand what they do, only that they are advertised as reducing power consumption.
My main question is, with FreeNas, would I be able to utilize these features? It's my understanding that whatever "p-states" are, are intel-specific hardware-set states that I can't change myself, and "c-states" are core-specific states that can be set by commands from the BIOS/OS. is that correct? Would I be able to change the c-state of several cores to shut some down when I am away? Are there other power saving features I could utilize besides states? If I were to change c-states on my Opterons, would that have any effect on power usage? Right now, if I query the system for c-state ability, I get this response for every core:
Code:
dev.cpu.0.cx_method: C1/hlt dev.cpu.0.cx_usage_counters: 92752345 dev.cpu.0.cx_usage: 100.00% last 6870us dev.cpu.0.cx_lowest: C2 dev.cpu.0.cx_supported: C1/1/0
I'm not sure how to interpret these lines. Could I change anything to shut down some cores while I shop for a new system?