sysctl hw.cpufrequencyIt should come back with the speed which your CPU is currently running at.
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If you feel your machine is acting a bit sluggish, you can check what speed the CPU is moving at by typing in the following in the Terminal:
sysctl hw.cpufrequencyIt should come back with the speed which your CPU is currently running at.
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Display your CPU's true speed
Interesting to see this posted as a hint, since it's known not to accurately report 12" Powerbook CPU speeds. There are threads in the forums that have thoroughly discussed this. In particular, on the 867MHz Powerbooks, sysctl seems to consistently report 533MHz, rather than the true 867MHz.
Display your CPU's true speed
hw.cpufrequency is also no official paramater for sysctl. It is not listed in the manpage.
Display your CPU's true speed
*whew* i thought mine was underclocked there...
Display your CPU's true speed
It also fails to display the correct CPU speed for 1 Ghz powerbooks, displaying 667 Mhz regardless of actual CPU speed.
Display your CPU's true speed
That's what it says for my 867 MHz powerbook too.
Display your CPU's true speed
It's lying.
Display your CPU's true speed
You mean like the Isuzu engine in a Chevy? Or a Ford engine in a Mazda and a Mazda engine in a ford? Or maybe a Volkswagen plant in an Audi?
Chevy and Oldsmobile have been the same company for many many years, and most Chevy/Oldsmobile vehicles - heck, GM vehicles, share parts and factories. Remember the Chevy Nova, Olsmobile Omega, and Pontiac [can't remember the name] - essentially the exact same car with slight grill and taillight/bumper styles. How about the Ford Taurus and the Mercury Sable? Or the Chevy truck / GMC truck? To better fit THIS situation, it would have to be like Chevy selling you a 300HP motor in a car, and listing it as 300HP, and putting all of the "300 HP" badges on the car and engine compartment - but only actually giving you a 250HP engine... Or maybe giving you an engine that can be 300HP but most of the time runs at 200HP... Something like that... I guess it could be like a car with a governor...
Display your CPU's true speed
My 1Ghz Powerbook comes out fine...
Display your CPU's true speed
That's what I get too
Display your CPU's true speed
What the !@#$? Ok, so I typed it in, and I get this back.
I thought perhaps I had the Energy Saver options set wrong. Nope, my 867Mhz 12" Powerbook is plugged in and set for "Highest" processor performance. Then it occurred to me, maybe you need to run it as root. So it tried a Sudo as well. Same response. So why is it telling me its running at 533Mhz? This is unacceptable! Something's got to be wrong here. Either it's my Powerbook, or this command. Please help!
Display your CPU's true speed
Never-mind my previous comment. As I was typing some other people had already posted comments. It's good to know my Powerbook wasn't running at 533MHz. Thanx guys. =)
Display your CPU's true speed
If it does not display the correct speed, do a PMU reset and it should show the correct speed after that.
Display your CPU's true speed
Here's my question than, if it doesn't display the correct speed right now, does that mean its actually running slower than its supposed to? And resetting the PMU (I assume you mean Power Management Unit) should kick it back into gear and run your CPU at full speed again? So supposedly, many of us are running our computers had drastically slower speeds. Or, is sysctl just reading it wrong all the time. I'm very curious to know the answer to this one. In the mean time I'm going to reset my PMU and see if that fixes it.
Display your CPU's true speed
systcl reports the wrong info. you can see how it does this by typing
in your Terminal. In the results you will notice that the numbers hw.cpufrequency, hw.cpufrequency_min, and hw.cpufrequency_max will be reported as all the same. I actually wrote a little Applescript called CPUfrequency that used systcl to "diagnose" whether the PMU needed to be reset. Shortly after releasing it to the world, I was lambasted with emails and comments stating that systcl is faulty and therefore my scripts don't really work. If Apple ever fixes sysctl, then the scripts will work and can be found here. If you look through the archives you will find more detailed discussion of why it does not work.
Display your CPU's true speed
Can someone that is seeing this issue run some benchmark that stresses the cpu heavily, and then reset the PMU, and run the same benchmark?
Display your CPU's true speed
Yippeee! Reseting the PMU works for me. Sysctl reads 866666664 now. So I wonder, how long have I been running at only 533Mhz? I'm amazed that this could even happen. I would think that "About this Mac" should always give you the correct CPU speed, and not some arbitrary number. I'm a bit unhappy with Apple on this one. Shame shame.
Display your CPU's true speed
is it possible that the 'speed' being reported by the System Profiler is not a MEASURED speed, but rather a speed that is being returned based on a gestalt ID... eg: maybe when the machine runs tha System Profiler, rather than actually measuring the speed, it just rely's on an Identification stored on the logic board... I say this because i do NOT believe that the System Profiler will report anything less than your machine's TOP-RATED speed...
if you have a Powerbook that does cpu speed-switching while on-battery, then try this...
Plug the machine into ot's Power Adapter and set the machine to MAXIMUM performance in the Energy Setting Pref Pane... (This should be the MAX cpu speed for your machine)... now run Sys. Prof. It reports your machine's Max Speed (the speed your Model was NAMED as)
Now take your machine OFF wall-power by removing it from the Power Adapter and set your Energy setting to Low Power (if you have a machine that is capable of doing cpu speed-reduction it will drop to the lower cpu speed)... Then run System Profiler again...
I guarantee that your machine STILL reports the HIGHEST speed...
Because it is NOT measuring it... it is reporting the speed NAMED in your Powerbook's Model-Name... eg: an 867MHz TiBook is ALWAYS going to say 867MHZ even though it may be running at 667MHz..
Display your CPU's true speed
What is a PMU Reset, and how do you do it?
Display your CPU's true speed
Read this knowledgebase article. It tells you how, as well as telling you what's going on and why this is a last-resort option.
Display your CPU's true speed
Thanks Aranor,
Display your CPU's true speed
I don't know about everyone else, but if I reset the pmu and turn the computer on it does read the correct speed. Upon restart though, it reverts back to the old speed!!!!!!
Display your CPU's true speed
Another note, the speeds began to be displayed incorrectly starting with 10.2.8.
Display your CPU's true speed
My 800MHz PowerBook G4 showed 667MHz. I reset the power manager, and <i>it feels faster.</i>
Display your CPU's true speed
Yeah, but after a while it goes back to being 677 Mhz. Check and see !
Display your CPU's true speed
I noticed this as well.
Display your CPU's true speed
I too had a wrong value from this -- my 1ghz TiBook reported 667. A few google searches and a few failed PMU reset attempts later, it finally worked, and it's reporting my speed as 999999997.
Display your CPU's true speed
Thanks for this tip. Terminal reported 667 MHz for my PowerBook G4 800, and since the PMU reset it is like a brand new computer. Why is this happening?
The Final Answer
Ok listen up, this should answer many of your questions. Here's my setup:
867Mhz 12" Powerbook
OS X Panther 10.3.1
Xbench 1.1.3
I created a new account just for this test. This is mostly because my primary account has a bunch of stuff running in the background, and I wanted to make this as subjective as possible. So, after a fresh restart I logged into my newly created account and did a sysctl hw.cpufrequency and got back an answer of 533Mhz like everyone else. I ran Xbench on CPU test only and after several dozen tries, got an average of about 98.3 (It varies slightly). I than shutdown my powerbook, and reset the PMU. When I started it back up and logged into my special account and did a sysctl hw.cpufrequency test again, this time it said my CPU was running at 866MHz. Much better. I then ran Xbench again, and guess what. I got the EXACT same scores. Somewhere around 98.3. So, what does this tell me? sysctl doesn't tell you anything. Ignore it. In fact, just restarting my computer, not reseting the PMU, will give me different answers when I do a sysctl hw.cpufrequency. Sometimes I get 533MHz, sometimes I get 866MHz. So, at least on my 12" Powerbook, it doesn't matter. Any perceived speed increases are just in your head. Hope this helps. -- Ahbe
The Final Answer
This is great, could someone else verify this as well?
The Final Answer
I confirm this. My Tibook 1 ghz was reporting 667 mhz from sysctl. I ran XBench, then reset PMU and reran XBench....same scores to within 0.5%. I conclude sysctl is just reporting wrong numbers....there is no performance change.
The Final Answer
One more test I think would be informative:
Display your CPU's true speed
without doing anything, restting the PMU or restarting or any other voodoo it reports my iBooks speed perfectly. A few extraneous 0s after the 8 but still the right speed.
Display your CPU's true speed
Based on this tip, I tried man sysctl:
Display your CPU's true speed
its a bsd thing... but i think linux has it...
Display your CPU's true speed
Am I doing something wrong? I get...
Display your CPU's true speed
The command is
noti.e. the last character is a lower case L not the digit 1. I assume sysctl is short for "system control" or some such.
Display your CPU's true speed
Thanks. Everyone was making comments about fonts, which had be confused. You finally told me the problem, changed the "1" to an "l" and there it was. Thanks!
Display your CPU's true speed
Maybe it's just me, but I seriously think MacOSXHints should consider using a different font for \[code\] if '1' and 'l' are going to look identically the same - especially since many things are done in root and cannot be undone!
Display your CPU's true speed
They look plenty different to me.
Display your CPU's true speed
Ah, the disadvantages of being on a Windows computer.
Display your CPU's true speed
I am cross-platform, so I saw it on my PC and typed it on my Mac. But thanks.
Display your CPU's true speed
Taking a peek at the style sheet, macosxhints' preferred code font is Monaco, in which an "
l" is not easily mistaken for a "1".
Display your CPU's true speed
This computer doesn't have Monaco - or even VT100 :(
Display your CPU's true speed
This is what it looks like (lol):
http://www.mproud.com/myscreen.png http://www.mproud.com/land1.png This computer bites! >:P All the more reason to go home to my Mac!
Display your CPU's true speed
Strange. I have 2 PCs at work, both running 2K and using Mozilla or Thunderbird - all default installs, nothing customized in the OS or Mozilla, they look fine to me. Obviously different. Things that make you go Hmmmmm.....
Display your CPU's true speed
Don't know where those "y's" came from :-P
Display your CPU's true speed
heh heh.. i was gonna submit this a few weeks back when i got phpsysinfo-dev working under apache/php on my 10.3.1 12" powerbook g4... but i never got around to it.. and it seems i've been beaten to the punch :-)
NOT TRUE - Display your CPU's true speed
Don't bother with this hint, it's been well discussed in many other mac forums, there was an extremely long thread on apples discussion boards. The command returns an incorrect speed on a few powerbooks (and maybe others).
Display your CPU's true speed
I can't think of a case where Rob has ever withdrawn a hint. But this one should definitely be withdrawn and sent to the trash.
Yowsah!
My 1ghz TiBook has report 667 mhz since I got it in August. I figured that the numbers coming back were bogus, but after resetting the PMU it reports 1ghz (.999999997 mhz, actually) and it really snaps now.
Yowsah!
Read the above comments. This is most likely a psychological effect (either that, or your computer is generally snappier after a restart and you just haven't restarted in a while).
Yowsah!
I posted the comment above about this not being true, just to follow up. I also have a 1 Ghz Ti PB and it reported 667 and after a PMU reset it reported 1 Ghz. But! after another reboot it went back to 667 (which in general has been the behavior reported by every other PB owner).
Display your CPU's true speed
I would be willing to bet, that all of you are seeing the effects of Apple's new "Processor and Bus Slewing" technology at work. The basics of this technology, is that when the computer senses that it is only being used at a small portion of its capabilities, it slows the bus AND processor speeds down to conserve power, and reduce heat. When the computer detects a higher demand of the processor, it kicks back up to the faster speed. Since a lot of what we do with a computer would be the same speed running at 500 Mhz as 1 Ghz, who cares? Typing email, browsing the internet, typing command line commands, will likely put the computer into the slower speed, and when you check the system speed, it will show the slower speed. The reason you can't see the difference in most cases, and the benchmarks don't show any difference, is that the computer is able to make these adjustments efficiently enough, so that it is undetectable to the user. The following is excerpted from Apple's Developer page.
Display your CPU's true speed
I don't buy what Apple is trying to tell us here...."Don't pay attention to the clock speed returned in the terminal..." What are they hiding from us. Why is my 800 MHz PowerBook G4 really returning 677 MHz. Maybe they just want to avoid a class action? I want this problem resolved Now! Proof, not chatter !
Display your CPU's true speed
See my response to your previous post in this thread...
Display your CPU's true speed
I'm using a powerbook G4 867 mhz and my computer said that it was running at the slower clock speed. To test to see if there was any difference after resetting the PMU, i wrote the small simple program:
I ran this after compling using gcc -O2 -o test test.c
using the command line:
Before the PMU reset, the test completed in 30 seconds, and after the PMU reset, the test completed in 27.5 seconds. This is a 9% difference. I ran the test four times in each case.
As such, I think that it does make a difference. Does anyone have any suggestions for maintaining the faster speed?
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