Re: Problems with PAE kernel sort of solved.
On 25/07/11 04:47 PM, Bob Proulx wrote:
Frank McCormick wrote:
Camaleón wrote:
Frank McCormick wrote:
I have been having problems with the new series of PAE kernels. I could
never get them to boot on my machine (see bug #632734) .
You early adopter you. I haven't rebooted my machine to the new
kernel today yet. :-)
Personally I am using the 64-bit amd64 kernel and so I won't be able
to verify whether PAE is a problem with the new kernel or not since
PAE is only relevant to 32-bit kernels.
This morning I installed the "new" 3.0.0 kernel, and spent a half hour
changing BIOS settings in an attempt to get it to boot.
I assume that you could select the previous kernel and boot okay? It
would be a good thing to double blind test. That would be a good A-B
comparison test. Because it is possible that the old kernel fails to
boot now.
Yes, 2.6.38 and 2.6.39 have been booting for months now (and still
boots) without a
problem. It was only when PAE was introduced I started having the
no-boot problem
That is odd since hyperthreading really has little to do with
multi-core cpus. It is orthogonal to it. In many ways HT is an Intel
marketing breakthrough since it is not a feature of AMD processors so
if consumers ask for hyperthreading the sales force will direct you to
an Intel cpu. Otherwise it has little advantage.
That's what I thought but the more mysterious thing is why the PAE
kernel boots fine with hyper-threading turned off.
The problem is the system **seems** significantly slower than it was..a
costly trade-off to run the new kernel. I don't see the connection
between the PAE option the kernel now uses (and which my dual core CPU
supports) and hyper-threading. Can anyone enlighten me ??
I have since benchmarked the system informally..and it is VERY
slightly faster with hyper-threading on.
Yes, that I guess is why the system now "sees" only one CPU when I
have a dual core.
Did you *really* have a dual-core? Or did you have a single-core with
HT enabled? I think probably the latter based upon your description
so far.
This is what cat /proc/cpuinfo says:
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 2
model name : Intel(R) Pentium(R) 4 CPU 2.60GHz
stepping : 9
cpu MHz : 2593.647
cache size : 512 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 1
apicid : 0
initial apicid : 0
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pebs bts cid xtpr
bogomips : 5187.29
clflush size : 64
cache_alignment : 128
address sizes : 36 bits physical, 32 bits virtual
power management:
processor : 1
vendor_id : GenuineIntel
cpu family : 15
model : 2
model name : Intel(R) Pentium(R) 4 CPU 2.60GHz
stepping : 9
cpu MHz : 2593.647
cache size : 512 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 1
apicid : 1
initial apicid : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pebs bts cid xtpr
bogomips : 5187.63
clflush size : 64
cache_alignment : 128
address sizes : 36 bits physical, 32 bits virtual
power management:
What do you make of that ?? Looks like a single-core to me ?
I think now I know more about CPU's than I ever wanted to know:)
--
Cheers
Frank
Reply to: