which ubuntu dapper kernel better fits a xeon dual core?

[lyndros]

hi guys,

two questions:
1)
wich kernel better fits dapper on xeon dual core with ubuntu dapper ?
Currently i am using 2.6.15.29-server, smp supports seems working fine, 2 cpus brought up (2 cores), top shows only one cpu but seems a top issue because htop shows both cores.

i don't like wasting time compiling kernels wich is the best? 686-smp ? etc

2)
i have read that enabling hyperthreading make the server slower, that's true?


thks again

[falko]

Originally Posted by lyndros

hi guys,

two questions:
1)
wich kernel better fits dapper on xeon dual core with ubuntu dapper ?
Currently i am using 2.6.15.29-server, smp supports seems working fine, 2 cpus brought up (2 cores), top shows only one cpu but seems a top issue because htop shows both cores.

i don't like wasting time compiling kernels wich is the best? 686-smp ? etc

What does

cat /proc/cpuinfo

show?

[lyndros]

here we go:

$cat /proc/cpuinfo

processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 15
model name : Intel(R) Xeon(R) CPU 3050 @ 2.13GHz
stepping : 2
cpu MHz : 2133.597
cache size : 2048 KB
physical id : 0
siblings : 1
core id : 255
cpu cores : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
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 nx lm pni monitor ds_cpl vmx est tm2 cx16 xtpr lahf_lm
bogomips : 4271.58

processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 15
model name : Intel(R) Xeon(R) CPU 3050 @ 2.13GHz
stepping : 2
cpu MHz : 2133.597
cache size : 2048 KB
physical id : 1
siblings : 1
core id : 255
cpu cores : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
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 nx lm pni monitor ds_cpl vmx est tm2 cx16 xtpr lahf_lm
bogomips : 4267.11

Both kernels -server & -686 brought me up 2 cpus, so cores seem to be running fine, but wich are the differences, wich better fix a dual core xeon.

thks in advanced

[edge]

Not sure if it will help you, but within TOP you can press 1 to toggle SMP view.

I'm using 2.6.8-3-686-smp on my dual Xeon servers (running Debian Edge)

cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 4
model name : Intel(R) Xeon(TM) CPU 2.80GHz
stepping : 3
cpu MHz : 2800.430
cache size : 2048 KB
physical id : 0
siblings : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 5
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 nx lm pni monitor ds_cpl cid
bogomips : 5554.17

processor : 1
vendor_id : GenuineIntel
cpu family : 15
model : 4
model name : Intel(R) Xeon(TM) CPU 2.80GHz
stepping : 3
cpu MHz : 2800.430
cache size : 2048 KB
physical id : 0
siblings : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 5
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 nx lm pni monitor ds_cpl cid
bogomips : 5586.94

processor : 2
vendor_id : GenuineIntel
cpu family : 15
model : 4
model name : Intel(R) Xeon(TM) CPU 2.80GHz
stepping : 3
cpu MHz : 2800.430
cache size : 2048 KB
physical id : 3
siblings : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 5
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 nx lm pni monitor ds_cpl cid
bogomips : 5586.94

processor : 3
vendor_id : GenuineIntel
cpu family : 15
model : 4
model name : Intel(R) Xeon(TM) CPU 2.80GHz
stepping : 3
cpu MHz : 2800.430
cache size : 2048 KB
physical id : 3
siblings : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 5
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 nx lm pni monitor ds_cpl cid
bogomips : 5586.94

[falko]

Originally Posted by lyndros

Both kernels -server & -686 brought me up 2 cpus, so cores seem to be running fine, but wich are the differences, wich better fix a dual core xeon.

That's hard to tell. I think the -server kernel has some optimizations for servers, so I'd go with that one, I think.

[Hans]

I use the Linux kernel 2.6.8-12-em64t-p4-smp.
This kernel is for Intel EM64T SMP systems and works flawless on my Dell servers with Intel dual Xeon processors and Debian Etch.

How i installed the kernel for Debian is decribed here": http://www.howtoforge.com/forums/showthread.php?t=19465

[lyndros]

Originally Posted by falko

That's hard to tell. I think the -server kernel has some optimizations for servers, so I'd go with that one, I think.

the problem is that ubuntu by default runs -server kernel so i am afraid that this is the most compatible so some enhancements has been disabled.

wow i dont know that about top, pressing 1 to toggle (thks)

thk u very much guys