Quite possible.I'll venture an opinion and say it's Hyperthreading. Turn off HT and see how that works out.
At any rate, the code is new, and isn't adjusted for the Nehalem processors. 
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Audio Decoding KILLS MacPro (2009) green factor
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At any rate, the code is new, and isn't adjusted for the Nehalem processors. 
Perhaps there are some problems in the Nehelem CPU power management of Snow Leopard.
The system seems to behave correctly when idling but it puts the CPU in its maximum power state as soon as there is a slight activity... Probably Snow Leo does not (yet) support every power saving feature of these CPUs correctly.
The system seems to behave correctly when idling but it puts the CPU in its maximum power state as soon as there is a slight activity... Probably Snow Leo does not (yet) support every power saving feature of these CPUs correctly.
Turn off HT and see how that works out.
yes.
not possible.
Download the free XCode Tools from Apple and install the Processor preferences pane.
This does not work for me in Snow Leopard. Even after disabling all but one of the CPUs, the CPUs still showed activity in activity monitor. I even rebooted after changing the settings and the settings reset themselves back to default. The hyper-threading setting seems to not work the same way. I'm only getting activity on 4 cores whether the setting is checked or not. I understand SL only utilizes hyper-threading under extreme CPU load, and that it makes conservative use of HT technology.
Maybe I'm doing something wrong, but it's not working for me. Maybe I don't know what I should be looking for?
Just to clarify... This happens on Leopard as well as Snow Leopard...
What I really need to do, or find someone who has.... is venture into the bootcamp world with a copy of XP or vista... and to repeat and see if its a hardware issue or a Operating system issue....
Someone was reporting similar issues over on the Apple support forums and I believe they did not experience the issue under Windows/Bootcamp. My question is whether this is really such a big deal? The CPUs are designed to get pretty hot, so a 10C jump in temps doesn't seem that unusual. The Core i7 PC overclockers typically run their i7s just under 100C under load. That's a lot hotter than what you're seeing without any real problems.
If we were looking at a 10(c) rise in temp, I'm cool with that. But many single core users, including myself, are seeing a 30(c) rise in temp. This is only on 2009 mac pro, not 2008 or 2007.
Correct me if I'm wrong. Higher heat is a result of higher voltage use. I'm not comfortable, nor should any user be with a CPU running out of control when just playing audio.
Apple touts their GREEN factor across their product lines. This CPU is supposed to be faster and run cooler.
The best thing about this is that the new iMacs will probably use variants of the i7 CPUs. Which should present the same behaivor. Bringing this issue to the forefront.
A CPU running hot with no necessary function beyond it just makes no sense and will only lead to issues down the road.
Hmmm I just visited my system prefs and I don't even see the processor pane. This is the fist I looked for that since I installed SL. Hmmm... Crap!
That's one way, and is applicable to Over Clocking in particular.
Another is to use more clock cycles to perform a task. The longer a core remains active, the higher the temp. If the load is 100%, then it will run at it's full thermal rating for the conditions (CPU used, ambient temp, cooling,...).
But the core isn't at 100%... It reports 1%.... Why would a CPU hit near 100% load temps @ 1%?
If I think of it when I get home tonight, I'll try this on my 2009 quad. I have both SL and Windows 7 RC on it so I'll try both (although I don't know how I'll measure temp on the windows side, but I should be able to get CPU %.)
30C is pretty high -- I see a 10C-15C rise when playing a song in iTunes. Closer to 15C when I have the visualizer enabled, closer to 10C without. You mentioned that "many single core users, including myself, are seeing a 30(c) rise in temp". You are only using a single core? Have you disabled the other three cores?
Do you still have the original CPU that came with your Mac Pro? I'm curious whether you experience this issue if you put the original CPU back? Also, how did you apply the thermal paste on your Core i7?
It shouldn't, but is why I recommended you re-seat the processor, as the pins may be "off center", giving bad thermal data (diode on die). It would help rule that out at any rate.
Just stopped by my local apple store and casually spoke with my business rep about the issue. 2 minutes later we had istat menu installed and within a short while the temp went from 33(c) to 52(c) and was still climbing.
He couldn't believe what he was seeing. Also considered it abnormal behaivor and is going to do some digging and call into apple engineering tomorrow.
He couldn't believe what he was seeing. Also considered it abnormal behaivor and is going to do some digging and call into apple engineering tomorrow.
Really? I mine never gets that low unless I ramp up the fans then I have to put up with the noise!
Really? I mine never gets that low unless I ramp up the fans then I have to put up with the noise!
Yep... I guess I have a lucky batch of CPU's... Then again I took that reading just after installing a copy of SL Server and the machine was truly running idle... My 2009 is running idle at 31(c) right now.
Was reading over at HardOCP about cooling the i7 CPU.
The temps they are seeing at 100% load are lower than playing iTunes on a 2009 mac pro. This is far from normal.
http://hardocp.com/article/2009/10/15/intel_core_i7_cooler_review/5
This illustrates the bad shape the 2009 MacPro is in. I entered a bug into Apples system over on ADC.
The temps they are seeing at 100% load are lower than playing iTunes on a 2009 mac pro. This is far from normal.
http://hardocp.com/article/2009/10/15/intel_core_i7_cooler_review/5
This illustrates the bad shape the 2009 MacPro is in. I entered a bug into Apples system over on ADC.
This surprises me as well. I even went back and checked the entire thread, and no-one's tried it yet.
But my gut tells me it's software (not optimized for Nehalem, or at least not properly).
It's been a long time since I have studied this but unless the CPU had a dedicated path for audio decoding, which to the best of my knowledge is not the case, it almost certainly has to be a software issue. Somehow the chipset is not being managed properly when decoding audio which should be totally fixable with drivers. The question is, does Apple actually acknowledge or care?
Was reading over at HardOCP about cooling the i7 CPU.
The temps they are seeing at 100% load are lower than playing iTunes on a 2009 mac pro. This is far from normal.
http://hardocp.com/article/2009/10/15/intel_core_i7_cooler_review/5
This illustrates the bad shape the 2009 MacPro is in. I entered a bug into Apples system over on ADC.
The temps they are seeing at 100% load are lower than playing iTunes on a 2009 mac pro. This is far from normal.
http://hardocp.com/article/2009/10/15/intel_core_i7_cooler_review/5
This illustrates the bad shape the 2009 MacPro is in. I entered a bug into Apples system over on ADC.