Core i7 950 3.02ghz can't see all cores

[davidwrivers]

Hi there,

So, I'm going a little bit crazy... I've successfully installed 10.6.2, and it's working great, except that in the 'about this mac' more info box, it says Number of Processors = 1 and Total Number Of Cores = 4

I'm booting with the cpus=1 flag. So, I'm trying to get it to see all 8 cores. I've patched the DSDT, removing the aliases for the processors (there were 8).

I can't seem to get away from this behaviour; whenever I start without the cpus=1 flag, the OS is ridiculously sluggish - it works, just, but it's so slow. Here's the weird part, if I wait long enough for the more info box, when booting without cpus=1, I still see processors = 1 and cores = 4!

I've placed the DSDT in the root, then tried in the extras folder as well... played with bios settings, but can't get it to run smoothly

It works so well with the cpus=1 flag, but so badly without, and it still doesn't see my full processor!

My mobo is an MSI x58 Eclipse, with 12gb RAM. I have an i7 950 3.02ghz CPU

Does anyone have any ideas to get my processor fully working?

Best
D

 

[FatShenanigans]

Hi there,

So, I'm going a little bit crazy... I've successfully installed 10.6.2, and it's working great, except that in the 'about this mac' more info box, it says Number of Processors = 1 and Total Number Of Cores = 4

I'm booting with the cpus=1 flag. So, I'm trying to get it to see all 8 cores. I've patched the DSDT, removing the aliases for the processors (there were 8).

I can't seem to get away from this behaviour; whenever I start without the cpus=1 flag, the OS is ridiculously sluggish - it works, just, but it's so slow. Here's the weird part, if I wait long enough for the more info box, when booting without cpus=1, I still see processors = 1 and cores = 4!

I've placed the DSDT in the root, then tried in the extras folder as well... played with bios settings, but can't get it to run smoothly

It works so well with the cpus=1 flag, but so badly without, and it still doesn't see my full processor!

My mobo is an MSI x58 Eclipse, with 12gb RAM. I have an i7 950 3.02ghz CPU

Does anyone have any ideas to get my processor fully working?

Best
D

Post your DSDT. I won't be able to look at it right away but I'll see what I can do. One thing I'm positive of is that the number of cores showing up is correct since you only have 4 physical cores but 8 virtual - OSX doesn't count the other 4 for System Profiler.

If you took out the aliasing it's strange that your system runs fast when you boot with cpus=1 but it might be something totally unrelated such as a hard drive problem that seems like a CPU problem.

 

[humph]

Core i7 950 only has 4 real cores...
But 8 (4+4 "virtual" cores) if you enable Hyperthreading in BIOS, perhaps it's not automatically turned on, or did you try that?

Scenario A)
But having Hyperthreading off (ie: 4 cores only) ought not to lead the the poor performance you describe. Is that only when cpus=1, and it's fine when you don't force that? If so, Hyperthreading...(or error in DSDT).

Scenario B)
Bad performance on 4 cores: Did you roll your own DSDT modding from eg: live linux CD dump, or grab someone else's? Just wondering if the 12GB memory is a problem, if you had a DSDT from someone with say 4GB...thought I read somewhere in Intel docs that memory map is altered when you have lots of memory.

 

[davidwrivers]

Thanks for the quick reply guys, appreciate it

Core i7 950 only has 4 real cores...
But 8 (4+4 "virtual" cores) if you enable Hyperthreading in BIOS, perhaps it's not automatically turned on, or did you try that?

I do have hyperthreading enabled in my bios - was running Win7 with all 8 just great. But, where's the fun in that...

Did you roll your own DSDT modding from eg: live linux CD dump, or grab someone else's?

I used DSDT_Patcher1.0.1e and then edited the aliases out by hand. I don't really understand the rest of the DSDT file, just that I've got to remove the aliases. Strangely, the DSDT file doesn't seem to have any kind of effect, other than it changes the name of the processor in the About This Mac box to Quad Core Xenon, whereas without the DSDT file, it reports a Core i7 950.


I noticed something when booting in verbose mode without the cpus=1 flag, and I got Unsynchronized TSC for CPU2, CPU 4, CPU 6 and CPU5 (in that order). Apparently this has something to do with the Kernel... it's all news to me


DSDT file attached - wasn't sure if it was the dsl or aml so put up both - any help is much appreciated

dsdt.dsl
DSDT.aml


Best,
D

 

[humph]

This bit in the dsl looks strange:
Scope (_PR)
{
Processor (P001, 0x01, 0x00000810, 0x06) {}
Processor (P002, 0x02, 0x00000000, 0x00) {}
Processor (P003, 0x03, 0x00000000, 0x00) {}
Processor (P004, 0x04, 0x00000000, 0x00) {}
Processor (P005, 0x05, 0x00000000, 0x00) {}
Processor (P006, 0x06, 0x00000000, 0x00) {}
Processor (P007, 0x07, 0x00000000, 0x00) {}
Processor (P008, 0x08, 0x00000000, 0x00) {}
}

I'm thinking it ought to have ...810 0x06 for each core.

Also, Chameleon defaults the processor ID to Xenon for >=4 cores, if it has a DSDT and/or smbios.plist to use to over-ride the BIOS info, or something like that.
(Then again, w/o a smbios.plist or DSDT, Chameleon will usually insert default parameter of Xenon if it sees >=4 cores). Anyway, that area is where the Xenon thing is coming from.

There's a thread here somewhere about adding SMcpuid to your smbios.plist to get i7 back in SysProfiler, or you can compile your own version of Chameleon with edit to the CPU detection code (that's mentioned in another thread...!).

 

[davidwrivers]

Thanks Humph,

I tried changing all the cores to 0x00000810, 0x06 but to no avail

I'm thinking it might be more to do with the Unsynchronized TSC stuff I see in -v boot mode. Apparently the only way to fix that is another kernel?

The strange thing is, that even when I boot without the DSDT and without the cpus=1 flag, it will boot, but the 'about this mac' box still says 1 processor/4 cores

Geekbench score of 3146 or something confirms that I'm only using a small percentage of this badass CPUs power

Thanks for the tips - do you think it's a BIOS setting? I haven't tweaked much there, but it seems if I change anything at all I get a KP.

Best,
D

 

[tonymacx86]

Just a suggestion- but maybe boot without DSDT, do a fresh extract using DSDTSE, and compare the CPU section- I agree that something looks off there.

 

[humph]

I'd try reinstall the stock kernel, as well as double check BIOS settings.

Don't really understand this multicore TSC stuff, but wonder whether HPET also may have impact? (Ensure is on and set to 64bit in BIOS).

And yes, grab a plain DSDT (I always do that via a LiveCD of Ubuntu) so you have a benchmark for comparisons.